[Footnote 1: "Physiologic Pathologique," Paris, 1828, t.i., p. 44.]
Bégin's definition scarcely separates idiosyncrasy from temperament, whereas, according to what would appear to be sound reasoning, based upon an enlarged idea of the physiology of the subject, a very material difference exists.
Idiosyncrasies are often hereditary and often acquired. Two or more may exist in one person. Thus, there may be an idiosyncrasy connected with the digestive system, another with the circulatory system, another with the nervous system, and so on.
An idiosyncrasy may be of such a character as altogether to prevent an individual following a particular occupation. Thus, a person who faints at the sight of blood cannot be a surgeon; another, who is seized with nausea and vomiting when in the presence of insane persons, cannot be a superintendent of a lunatic asylum--not, at least, if he ever expects to see his patients. Idiosyncrasies may, however, be overcome, especially those of a mental character.
Millingen[1] cites the case of a man who fell into convulsions whenever he saw a spider. A waxen one was made, which equally terrified him. When he recovered, his error was pointed out to him. The wax figure was put into his hand without causing dread, and shortly the living insect no longer disturbed him.
[Footnote 1: "Curiosities of Medical Experience," London, 1837, vol. ii., p. 246.]
I knew a gentleman who could not eat soft crabs without experiencing an attack of diarrhea. As he was exceedingly fond of them, he persevered in eating them, and finally, after a long struggle, succeeded in conquering the trouble.
Individuals with idiosyncrasies soon find out their peculiarities, and are enabled to guard against any injurious result to which they would be subjected but for the teachings of experience.
Idiosyncrasies may be temporary only--that is, due to an existing condition of the organism, which, whether natural or morbid, is of a transitory character. Such, for instance, are those due to dentition, the commencement or the cessation of the menstrual function, pregnancy, etc. These are frequently of a serious character, and require careful watching, especially as they may lead to derangement of the mind. Thus, a lady, Mrs. X, was at one time under my professional care, who, at the beginning of her first pregnancy, acquired an overpowering aversion to a half-breed Indian woman who was employed in the house as a servant. Whenever this woman came near her she was at once seized with violent trembling, which ended in a few minutes with vomiting and great mental and physical prostration, lasting several hours. Her husband would have sent the woman away, but Mrs. X insisted on her remaining, as she was a good servant, in order that she might overcome what she regarded as an unreasonable prejudice. The effort was, however, too much for her, for upon one occasion when the woman entered Mrs. X's apartment rather unexpectedly, the latter became greatly excited, and, jumping from an open window in her fright, broke her arm, and otherwise injured herself so severely that she was for several weeks confined to her bed. During this period, and for some time afterward, she was almost constantly subject to hallucinations, in which the Indian woman played a prominent part. Even after her recovery the mere thought of the woman would sometimes bring on a paroxysm of trembling, and it was not till after her confinement that the antipathy disappeared.
Millingen[1] remarks that certain antipathies, which in reality are idiosyncrasies, appear to depend upon peculiarities of the senses. Rather, however, they are due to peculiarities of the ideational and emotional centers. The organ of sense, in any one case, shows no evidence of disorder; neither does the perceptive ganglion, which simply takes cognizance of the image brought to it. It is higher up that the idiosyncrasy has its seat. In this way we are to explain the following cases collected by Millingen:
[Footnote 1:Op cit., p. 246.]
"Amatus Lusitanus relates the case of a monk who fainted when he beheld a rose, and never quitted his cell when that flower was blooming. Scaliger mentions one of his relatives who experienced a similar horror when seeing a lily. Zimmermann tells us of a lady who could not endure the feeling of silk and satin, and shuddered when touching the velvety skin of a peach. Boyle records the case of a man who felt a natural abhorrence to honey; without his knowledge some honey was introduced in a plaster applied to his foot, and the accidents that resulted compelled his attendants to withdraw it. A young man was known to faint whenever he heard the servant sweeping. Hippocrates mentions one Nicanor, who swooned whenever he heard a flute; even Shakespeare has alluded to the effects of the bagpipes. Julia, daughter of Frederick, King of Naples, could not taste I meat without serious accidents. Boyle fainted when he heard the splashing of water; Scaliger turned pale at the sight of water-cresses; Erasmus experienced febrile symptoms when smelling fish; the Duke d'Epernon swooned on beholding a leveret, although a hare did not produce the same effect; Tycho Brahe fainted at the sight of a fox; Henry III. of France at that of a cat; and Marshal d'Albret at a pig. The horror that whole families entertain of cheese is generally known."
He also cites the case of a clergyman who fainted whenever a certain verse in Jeremiah was read, and of another who experienced an alarming vertigo and dizziness whenever a great height or dizzy precipice was described. In such instances the power of association of ideas is probably the most influential agent in bringing about the climax. There is an obvious relation between the warnings given by the prophet in the one case, and the well-known sensation produced by looking down from a great height in the other, and the effects which followed.
Our dislikes to certain individuals are often of the nature of idiosyncrasies, which we can not explain. Martial says:
"Non amo te, Sabidi, nec possum dicere quare;Hoc tantum possum dicere, non amo te;"
or, in our English version:
"I do not like you, Doctor Fell,The reason why I can not tell;But this I know, and that fullI do not like you, Doctor Fell."
Some conditions often called idiosyncrasies appear to be, and doubtless are, due to disordered intellect. But they should not be confounded with those which are inherent in the individual and real in character. Thus, they are frequently merely imaginary, there being no foundation for them except in the perverted mind of the subject; at other times they are induced by a morbid attention being directed continually to some one or more organs or functions. The protean forms under which hypochondria appears, and the still more varied manifestations of hysteria, are rather due to the reaction ensuing between mental disorder on the one part, and functional disorder on the other, than to that quasi normal peculiarity of organization recognized as idiosyncrasy.
Thus, upon one occasion I was consulted in the case of a lady who it was said had an idiosyncrasy that prevented her drinking water. Every time she took the smallest quantity of this liquid into her stomach it was at once rejected, with many evident signs of nausea and pain. The patient was strongly hysterical, and I soon made up my mind that either the case was one of simple hysterical vomiting, or that the alleged inability was assumed. The latter turned out to be the truth. I found that she drank in private all the water she wanted, and that what she drank publicly she threw up by tickling the fauces with her finger-nail when no one was looking.
The idiosyncrasies of individuals are not matters for ridicule, however absurd they may appear to be. On the contrary, they deserve, and should receive, the careful consideration of the physician, for much is to be learned from them, both in preventing and in treating diseases. In psychiatrical medicine they are especially to be inquired for. It is not safe to disregard them, as they may influence materially the character of mental derangement, and may be brought in as efficient agents in the treatment.--N.Y. Medical Journal.
[Footnote: Abstract from a paper lately read before the Southern Dental Association, Baltimore, Md.]
A gentleman, a physician, aged thirty-two years, strong and vigorous, with no lack of nerve-energy, calls to have his teeth attended to, with the disease in the first stage throughout the mouth. Upon examination, he observes upon the gum of one of the lower cuspids a dark purplish ring encircling the neck, from one-sixty-fourth to one sixteenth of an inch in depth; the toothin situis white and clean. With the aid of the mouth and hand mirror he shows the condition to the patient, and, taking up an excavator, endeavors to pass it down between the tooth and gum, on the labial surface. After it gets down a little way the instrument meets with an obstruction, over which, calling the patient's attention to the fact, he carefully guides the instrument until it drops down on the tooth-substance beyond it; then, turning the instrument and pressing it upward, he breaks off a portion of the concretion; which proves to be what is ordinarily called lime-salts, or tartar. That is the cause of the purple ring on the gum, which is merely the outward manifestation of the disease. Take it off thoroughly, polish the surface of the tooth, and in three days' time the gum will show a perfectly healthy color. The condition described is the first stage of the disease, and the treatment given is all that is required for a cure of the case at this time. But take the same man and let him go for ten years without the simple operation detailed. The disease spreads, and causes inflammation of the process, and, finally, its absorption--sometimes on the labial surface for one half or two-thirds the length of the tooth. It runs its course, the tartar accumulating, all the time following up the line of attack. At the end of ten years what has become of the line of tartar? Sometimes it will be found extending clear around the tooth. Sometimes it will not be found at all; it has done its work--the tooth is loose, but the concretion is gone, in whole or in part. In this case the patient wants the tooth out, but, he asks, what has become of the tartar? The answer is that the natural acids found in the oral cavity have dissolved it, and it has passed into the stomach or out of the mouth in the saliva. But the tooth is so loose that it is a torment to the man; it lies in its socket, entirely loose, almost ready to drop over. It hurts so that he cannot bear the pain. The tooth is taken out. There is no tartar on it, or very little; there is a little speck near the point that looks like a foreign body; but the point of the tooth--the apex--is as sharp as a needle. After the disease has done its work of separating the tooth from its socket, the destroying agent begins to absorb the tooth at the point, irregularly, causing the sharpness described. Now, because no tartar is found upon the tooth, does that argue that it has never been there? Not at all; the loosened tooth shows simply that it has been there and has been absorbed. The speaker has never seen a tooth in that condition on the point of which he could not show patches or specks; we may not see the tartar, but it certainly once existed there, and has accomplished its work.
Now suppose we find a patient with all the teeth loosened; he has neuralgia pains in the face, for which medicine seems to furnish no remedy; he has also catarrh, and the malar and nasal bones are all affected. In the third and fourth stages a low inflammatory action pervades all the bones of the face, accompanied by neuralgic pains, extending to the brain itself. In such a case the disease of the teeth intensifies the catarrh. A medical man called upon him for treatment for pyorrhea alveolaris; the patient was also afflicted with catarrh. He cured the pyorrhea alveolaris, and cured the catarrh, too, at the same time.
Another case.--A lady called in great distress. Nearly all her teeth were affected, and the discharge was most offensive and abundant; if she lay on her side in bed, the pillow would be covered with large splotches of the discharge in the morning; if she lay on her back, the mass was swallowed, and the result was that the whole alimentary canal was demoralized by the pus, blood, and vitiated secretions. When she arose she wanted no breakfast, only two or three cups of strong coffee and some crackers. She was nearly blind, could only see a great light, and was totally unable to see to read. He told her that the trouble with her sight was caused by the diseased condition of the teeth; that unless that was remedied, she might live three months, but she would die suddenly. He treated three or four teeth at a time at each sitting. This consumed three weeks. The teeth became firm, her appetite returned, her sight was restored, and she was able to walk a mile or two without disturbance. He was called to Brooklyn, where they had a live society, and an infirmary for the treatment of dental diseases, at which members of the society were delegated to attend from day to day. He was invited to give a clinic upon pyorrhea alveolaris, and he told them of this patient, whom he showed to some fifteen members. The woman was apparently in fair health. It was not loss of nerve-energy which started the disease in this case, but the disease caused the loss of appetite and the vitiated condition of the whole alimentary canal. Her physician would have sent this woman to the grave, not recognizing the disease and its management.
He maintains that it is not lack of nervous energy that causes this disease, but the disease will lead to loss of nerve-energy. That small purple ring on the gum of the cuspid in the case first mentioned would eventually have led to the loss of the whole set, if left to work its way unopposed. He had tried in these remarks to controvert the old ideas, and to present the cause of the disease and its treatment as he sees it. You may see it differently; if so, give us your information, in order that we may correct our views, if wrong.
One gentleman says he finds it is only those who are strong and vigorous who have this disease. The speaker finds some cases of this kind; he also finds consumptives who have not a trace of it, but he would take the strongest man in the room and cause a beautiful case of pyorrhea alveolaris in his mouth in three weeks, with a fine cotton thread tied around one of the lower front teeth at the line of the gum. The thread will work its way under the gum, and the gum will become inflamed; it will work its way down between the gum and the tooth, and in the meantime the flour and the particles of food will also work down under the loose gum, finding a rallying-point on the thread; the mass will become impregnated with lime-salts, and will then begin to harden, and in a very short time you will have an excellent example of the disease under discussion. Patients suffering from salivation fall an easy prey to this disease, due to the action of the drug on the glands and the hard and soft tissues of the mouth, the gums in such cases affording a ready pocket under their edges for the deposits.
When you find a tooth with the characteristic concretion of tartar upon it, the first principle of surgery demands that you clean that tooth thoroughly. Go down beyond the line of the disease, go around the tooth thoroughly, and break up the diseased tissue, and apply tincture of myrrh, and in three days you will notice a marked improvement for the better, and if the patient takes proper care of the teeth the disease will not return. Practitioners should watch the teeth of the young people under their care, and see that the mouth is kept scrupulously clean and healthy.
In reply to a question, Dr. Riggs stated that whenever absorption goes on irregularly, unless the inflammatory action is extreme, it will sometimes absorb one or two bone-cells, and then skip one or two, and these last, being isolated, naturally die, or become necrosed to some extent. In treating this disease you must break up the line of disintegrated tissue. You must, as it were, transfer your eyesight to the end of the instrument, so that when you strike dead bone you will know it. Live bone will feel smooth and greasy.
It requires some years of experience to treat this disease properly, because you have not your eyesight to aid you, but must depend absolutely upon the sense of touch. With experience, however, you will learn to give a great deal of relief in one of the most annoying conditions to which the teeth are subject. The reason the profession are not familiar with the treatment of this disease is, they fail to recognize it until it reaches its third or fourth stage, and then they treat it by depletion and therapeutic remedies. Some treat it by stippling in acids underneath the gum, thinking thereby to dissolve away not only the tartar, but the necrosed bone. Another writer takes off patches of the diseased tissue, and another a strip of the gum, from wisdom-tooth to wisdom-tooth. This treatment he could only characterize as simply barbarous. The treatment of this disease is purely surgical. Any therapeutic treatment is to alleviate the pain and soreness immediately after the operation.
Dr. W. N. Morrison, St. Louis, referring to the method of treating pyorrhea alveolaris described by Dr. Riggs, said he cheerfully bore testimony to the importance of loosening the scales of tartar, and teaching patients the value of cleanness of the mouth. In his experience he had found that all instruments will occasionally fail to dislodge the deposit. In such cases he used as an assistant a little ring of para gum about an eighth of an inch wide. This was sprung on the tooth at the edge of the gum. If this is done and the ring allowed to remain a few hours, you will see an entirely new revelation, and you will readily be able to get at the tooth to clean it. He had found it advisable to give patients practical showing how the brush should be used.
At a recent meeting of the Paris Academy, M. D'Abbadie called attention to some facts regarding marsh fever, which African travelers and others might do well to ponder. Some elephant hunters from plateaus with comparatively cool climate brave the hottest and most deleterious Ethiopian regions with impunity, which they attribute to their habit of daily fumigation of the naked body with sulphur. It was interesting to know whether sulphurous emanations, received involuntarily, have a like effect. From inquiries made by M. Fouqué, it appears that in Sicily, while most of the sulphur mines are in high districts and free from malaria, a few are at a low level, where intermittent fever prevails. In the latter districts, while the population of the neighboring villages is attacked by fever in the proportion of 90 per cent., the workmen in the sulphur mines suffer much less, not more than eight or nine per cent. being attacked. Again, on a certain marshy plain near the roadstead in the island of Milo (Grecian Archipelago), it is hardly possible to spend a night without being attacked by intermittent fever, yet on the very fertile part near the mountains are the ruins of a large and prosperous town, Zephyria, which, 300 years ago, numbered about 40,000 inhabitants. Owing to the ravages of marsh fever the place is now nearly deserted. One naturally asks how such a town grew to its former populous state. Sulphur mining has been an important source of wealth in Milo from the time of the ancient Greeks. Up to the end of last century the sulphur was chiefly extracted at Kalamo, but since that time it has only been mined on the east coast of the island. The decadence of Zephyria has nearly corresponded to this transference. The sulphurous emanations no longer reach the place, their passage being blocked by the mountain mass. Once more, on the west side of the marshy and fever-infested plain of Catania, traversed by the Simeto, is a sulphur mine, and beyond it, at a higher level, a village which was abandoned in the early part of this century because of marsh fever. Yet there is a colony of workmen living about the mine, and they seem to be advantageously affected by the emanations. M. D'Abbadie further mentions that the engineer who made a railway through this notorious plain preserved the health of his workmen by requiring them to drink no water but what was known to be wholesome and was brought from a distance.
Messrs. Laurent Bros. & Collot exhibited at the Paris Universal Exhibition in 1878 a patented hydraulic apparatus styled a filtering press, the principle and construction of which it will prove of interest to describe. The apparatus is remarkable for its simplicity and ease of manipulation, and is destined to find an application in most oil mills.
Details of Structure.--The filter, which is shown in detail in Figs. 5 to 7, is formed of two semicylindrical cast iron shells, F, that are firmly united, and held by a strong iron band which is cleft at one point in its circumference, and to which there is adapted a mechanism permitting of loosening it slightly so as to facilitate the escape of the oil-cake. Within these shells, F, there are grooves, a, which have the arrangement shown by the partial section in Fig. 11, and through which flows the oil expressed by pressure. To prevent the escape of the material through these grooves or channels, the interior of the shells is lined throughout with plates or strips of brass that fit very closely together, and present a simple slit with chamfered edges opposite the grooves. At the two joints of the shells four of these plates are riveted two by two; all the others are movable, and rest, like the pieces of an arch, against the fixed plates that form abutments. Each half lining is thus held by means of a central plate, b' (Fig. 10), with oblique edges, and which, being driven home by the top of the filter, binds the whole tightly together. All these plates, which are slightly notched at their upper part, rest on a small flange at the lower part of the shells.
FILTERING PRESS FOR OLEAGINOUS SEEDS.--AUTOMATIC INJECTION PUMP
FILTERING PRESS FOR OLEAGINOUS SEEDS.--AUTOMATIC INJECTION PUMP
As regards their manufacture, these plates are cut out of sheets of perfectly laminated brass, and are afterward set into a matrix to center them properly. After the shells have been bored out, all the plates are mounted therein so as to obtain a perfectly cylindrical and uniform surface. The plates are then numbered and taken out; and, finally, a slit with chamfered edges is cut longitudinally through them, save at three points--two at the extremities and one at the middle. The plates thereafter rest against each other only at these three points, and leave at the chamfered places capillary openings just sufficient to give passage to the oil, but not to the pressed paste, however fine it be. As will be seen in Fig. 5, the points of contact are not in the same horizontal plane, but are arranged spirally, so that the flow will not be stopped at this place as it would be were these solid parts all at the same height. The filter, F, is completed by two pieces that play an important part. The first of these is a cast iron rim, J, which is set into the upper edge, and forms a sort of lip whose internal diameter corresponds exactly to the surface of the plates, b. This rim, J, is cast in one piece, and carries on its circumference two small, diametrically opposite iron studs, which are so placed that they may engage in the groove, p, at the upper edge of the shells, F.
The second of the two pieces is a cast iron bottom, K, which works on a hinge-joint, and which is perforated with a large number of holes for giving passage to the oil that has traversed the hair cloth cushion of which we shall speak further on. These holes must correspond accurately with the radial conduits presented by plate, E, and through which flows the oil to a circular channel running around this same piece. In order to exactly maintain such a relation between the holes and channels, the piece, E, is provided with a stirrup-iron, d, that passes around one of the columns, C, of the hydraulic press.
The entire filter thus constructed is attached to one of the columns, C', of the hydraulic press in such a way that it can revolve around it. For this purpose, the column is surrounded by an iron sleeve, L, cast in two pieces, and which in its lower position rests on the shoulder, e, of the column. The filter is connected with the sleeve by means of screws, as shown in Fig. 6.
We shall now describe the mechanism for loosening the band, I, and moving the bottom, K.
The band, I (Figs. 5 to 9), is cleft at a point in its circumference corresponding to one of the joints of the shell, F, and carries at each side of the cleft a bearing in which turns freely a steel pin. One of these latter, i, is cylindrical, and the other, j, has eccentric extremities that are connected with the former by two small iron rods, k and l. The upper extremity of the pin, j, is provided with a bent lever-handle, M, and the lower one carries in its turn a small disk, m, the use of which will be explained further on. It results from such an arrangement that by acting on the lever, M, with the band, and by reason of the eccentricity of the pin, j, the two extremities of the band, I, may be made to approach or recede at the will of the operator. The position of nearest approximation is limited by the abutting of the hook at the end of the lever, M, against the side of the filter. This latter position corresponds to the moment of charging the apparatus (Fig. 6), while the contrary one indicates the moment that the oil cake falls (Fig. 4). Although the separation is but a few millimeters, it is sufficient for disengaging and allowing the cake to drop.
The movable bottom, K (Figs. 5 and 6), which closes the base of the filter during the pressing, becomes detached and drops vertically (Figs. 3 and 4), when the filter is disengaged from the press, and the oil cake is to be dropped out. To render the maneuver of this part easy, the bottom is provided with a projecting piece, N, united by a bolt with the band, I, and furnished with an articulated hand-lever, N', that terminates in an appendage, q. The upper part of the hinge is provided with a tail piece, q', under which the appendage q, places itself when the bottom, K, is brought to its horizontal position. Consequently, when the operator desires to let the bottom drop in the position shown by the dotted line (Fig. 5), after the filter has been loosened, he moves the lever, N, to the position shown by the dotted line (Fig. 6). The appendage, q, then disengages itself from the tail piece, q', and the bottom is thus enabled to assume a vertical position. As the bottom at the time of charging would not be sufficiently supported if there merely existed the lever and catch, it is further provided at its opposite extremity with an appendage, r, which slides over a catch, r'. This latter is attached to the disk, m, at the lower extremity of the pin, j (Fig. 7), and takes exactly the proper position when the band is closed at the moment of charging, but leaves it, on the contrary, when the band is loosened to allow the oil cake to drop out.
As the lateral flow takes place through the interstices of the brass lining, there is need of but one cushion on the bottom and another at the top to hold the material to be pressed. The first is a simple hair-cloth disk for preventing the seed from passing through the perforations in the bottom plate; and the second, O, of which Figs. 12 and 13 represent a segment, is formed of three thicknesses of the same material united at the edges by two flat iron circles, s, riveted together. These circles, which are made to fit the inside diameter of the shells very accurately, prevent any leakage of the oil around the presser, G, and keep the hairs from getting caught between this piece and the plates, b.
Charging of the Filter. (Figs. 14 and 15.)--The apparatus for charging the filter is of the same capacity as the latter, and is made of galvanized iron. It is placed on a slide at the aperture of the steam kettle so as to receive the warm seed as it is thrown out by the stirrer. When full, it is taken up by its handles, rested on the rim of the filter, and its contents emptied therein.
General Manipulation of the Press.--Supposing the filter in the position shown in Figs. 3 and 4, at the moment the seedcake is about to drop out: the operator takes hold of the lock lever, N, with his left hand, raises the bottom, K, to a horizontal position, and at the same time fastens the bolt of the lever by turning it. He then seizes the lever, M, with his right hand, and turns it so as to close the filter, having care at the same time to support the extremity, r, of the bottom with his left hand so that the catch, r', may pass under it when the lever is manipulated. The bottom haircloth is then put in place, the charge is thrown in, and its surface leveled, and the hair-cloth cushion is laid on top. The filter is then revolved around the column so as to bring it into the position shown in Fig. 1. The cock of the distributer that admits water under pressure being turned on, the ram, D, rises, carries with it the filter, and compresses the material against the presser, G. At the end of from six to ten minutes the pressure-valve is closed and the discharge-valve opened. The filter then slides down with its socket along the column, C', till it reaches the shoulder, e, where it rests. It is next swung around to the position shown in Fig. 3, and emptied of its contents by a manipulation, the reverse of that described for charging it. All these manipulations of charging and emptying require no more than half a minute on the part of an experienced workman.
The press under consideration is well adapted to the treatment of heated seed paste, and has been very successfully employed for that purpose in France, Belgium, and Holland. It succeeds equally well for the extraction of oil from nuts. Referring to the drawings, the scales are for Figures 1, 2, 3, 4, 14, 15, one fifteenth actual size; Figures 5, 6, 7, 8, 9, one-tenth; Figures 10, 11, 12, and 13, one-fifth.--Machines, Outils et Appareils.
As well known, in every well-constructed injection pump, there is a system of gearing which acts upon the suction valve and stops the operation of the pump as soon as the requisite pressure is reached; but the piston, for all that, continues its motion, and, besides the resistant work of the pump has passed through different degrees of intensity, seeing that at every moment of its operation the piston has preserved the same stroke and velocity. We are speaking, be it understood, of pumps that are controlled mechanically. In the one that we are about to describe, things take place far otherwise. In measure as the pressure increases, the stroke of the piston diminishes, and when it has reached its maximum, the motion of the piston ceases entirely. If, during the operation progression undergoes more or less variation, that is, for example, if it diminishes at a given moment to afterwards increase, the stroke of the piston undergoes all the influences of it.
The pump of which we speak is shown in Figs. 16 to 21, and is the invention of Messrs. Laurent Bros. & Collot. It may be described briefly as follows:
The apparatus, as a whole, has for base a cast-iron reservoir; A, to the top of which is fixed the pump properly so-called, B, as well as the clack box, A, and safety valve. The pump is placed opposite an upright, D, whose top serves as a guide to the prolongation, E, of the piston rod. This latter is traversed by a pivot, a (Fig 19), on which is mounted a lever, F, whose outer extremity is articulated with a connecting rod, G, which is itself connected with the cranked shaft, G¹. This shaft has for its bearings two supports, b, attached to the reservoir, and carries the driving pulleys and a fly wheel. The beam, F, having to give motion to the piston in describing an arc of a circle at the extremity attached to the connecting rod, must, for that reason, have a fixed point of oscillation, or one that we must consider as such for the instant. Now, such point is selected on a piece, H, having the shape of the letter C, and which plays an important part in the working of the pump. This piece is really a two-armed lever, having its center of oscillation in two brackets, c, at the base of the reservoir. Fig. 17 shows the relation of the beam, F, and lever, H. The upper extremity of this latter is forked, and embraces the beam, F, whose external surfaces are provided with two slots, d, in which to move slides, e, attached to studs, f, which are perfectly stationary on the extremities of the forks of the lever, H. One of the slots is shown in section on the line 1--2 in Fig. 20, and on the line 3--4 in Fig. 21.
Things thus arranged, if we suppose the piece, H, absolutely stationary, it is clear that, as the oscillation of the beam, F, is effected on the studs, f, as centers, the piston of the pump will perform an invariable travel whose extent will be dependent upon its position between such point of oscillation and the point of articulation of the connecting rod, G. But we must observe that even according to such a hypothesis, the point, f, would not be entirely stationary, because the point of articulation, a, upon the piston rod being obliged to follow an invariably straight line, the slots, d, will have to undergo an alternate sliding motion on the slides, e, save, be it understood, when the latter are brought to coincide exactly with the center of articulation, a. Now we shall, in fact, see that the point, f, can move forward in following the slots, d, and that it may even reach the point of articulation, a, of the beam, F, on the rod, E, that is to say, occupy the position shown in Fig. 18, where the oscillation of the beam, F, being effected according to the point, a, the stroke of the piston has become absolutely null.
The position of the piece, H, is, in effect, variable with the pressures that are manifested in the pump. It will be seen that the latter has a tubular appendage, g, in whose interior there plays what is called a "starting rod," h, which is constantly submitted to the pressures existing in the interior of the pump, and which rests against the lower arm, H¹, of the piece, H. But this latter is also loaded at the opposite side with heavy counterpoises, i, which counterbalance, within a determinate limit, the action of the rod, h, that tends constantly to cause the lever, H, to oscillate around its pivot, in the brackets, c.
To sum up, then, as long as the pressure in the pump has not reached a determinate limit, the lever, H, held by its counterpoises,i, will keep the position shown in Fig. 16, and for which the center of oscillation, f, corresponds with the maximum stroke of the pump piston. But as soon as such limit is exceeded, the equilibrium being broken, the action of the rod, h, predominates, the piece, H, reverses from right to left, the point of oscillation, f, moves forward in the slots, d, and the stroke of the piston is reduced just so much. If, finally, the pressure continues to increase, the motion of the piece, H, will continue, and the point of oscillation, f, will reach the position for which the motion of the piston ceases completely (Fig. 18).
But it results further, therefrom, that if when such position is reached, the pressure diminishes, the lever, H, will, under the influence of its counterpoise, tend to return to its first position and thus set the piston in motion. As we remarked in the beginning, the automatism of these functions is absolutely complete.
It will be remarked that the piece, H, is provided with an appendage, H², whose interior forms a rack. This rack engages with a pinion, I, mounted on an axle, J, which carries externally a fly wheel, K. This axle, J, moves with the various displacements of the lever, and its fly wheel overcomes by its inertia all backward and forward shocks resulting from the thrusts due to the sliding of the steel slides in the different positions of the connecting rods. Such shocks would make themselves especially felt while the dead centers were being passed.
The velocity with which this pump runs varies from 75 to 80 revolutions per minute. It easily gives a pressure of 200 atmospheres. With a hydraulic press having a piston O.27 of a meter in diameter, it permits of effecting in ten minutes the extraction of the oil from 25 kilogrammes of colza seeds. Referring to the drawings, the scales for Figures 16, 17, 18 are one-fifteenth actual size, and Figures 19, 20, 21, one-tenth.--Machines, Outils et Appareils.
We illustrate below a dredger of simple construction, well calculated for doing useful work on shallow streams. The barge is 54 ft. long, 22 ft. beam, and 6 ft. deep. Her draught of water is under 4 ft. Built by Rose, Downs & Thompson Hull. Our drawing explains itself. It will be seen that we have here a swiveling crane and grab bucket, and that the stuff dredged can be loaded into the barge and conveyed where necessary. The lifting power of the crane is one ton, and in suitable material such a dredger can get through a great deal of work in a comparatively short time.--Engineer.
IMPROVED ONE-TON BUCKET DREDGER.
IMPROVED ONE-TON BUCKET DREDGER.
The first fire extinguishers were of the "annihilator" pattern, so arranged in a building that when a fire occurred carbonic acid gas was evolved, and, if the conditions were right (as the mediums say), the fire was put out. It worked very nicely at experimental fires built for the purpose, but was apt to fail in case of an involuntary conflagration. About the year 1867 a patent was granted to Carlier and Vignon, of France, for an apparatus in which water saturated with carbonic acid gas was projected upon the fire by the expansive force of the gas itself. As the apparatus was portable and the stream could be directed to any point, it was obviously the desideratum needed. Mr. D. Miles, of Boston, purchased the American patent, and subsequently sold the territory, exclusive of New England, to the Babcock Co., who, at the time, had a crude apparatus of their own. The first machines sold under the new patent were filled with water and loaded with cartridges of dry acid and bicarbonate of soda--the cap screwed down hastily, and, as the chemicals dissolved, the gas was generated, the pressure raised, and the water charged by absorption. The pressure of some 80 pounds was sufficient to project a stream 50 feet or more, and the machine was set upon the shelf so as to be ready for any fire that might occur. In many cases, however, the pressure escaped after a short time, and the machine when needed was found to be useless.
The most important step in the evolution of the modern extinguisher was the adoption of a device for mixing liquid acid with the soda solution, by the turning of a handle or screw,afterthe alarm was given. This was a practical machine, and proved of such value that an immense business was built up. The result of this prosperity was the development of new companies with new devices for accomplishing the same result, which were successfully offered to the public with varying success.
As these were direct infringements upon the patent rights acquired by the Babcock Company, their encroachments were resisted in the courts, and much money was spent in the effort of the company to sustain their rights, including the purchase of the patents of several rival machines that possessed real merit or whose business was worth controlling. Among these purchases was the right and good will of the "National" Extinguisher Co., who used an acid cartridge of glass, the acid being liberated by breaking the glass. This feature, united with important improvements in general construction and the use of a peculiar glass bottle instead of a tube, is the Babcock machine of to-day, the combination making the simplest and most effective and reliable apparatus ever built. In the meantime, an investigation before the courts brought out the fact that the French patent was antedated by an American invention, for which a patent was applied by a Dr. Graham, in 1837. and which possessed the essential features of the principle in dispute. Graham, through lack of means, or for some other reason, had failed to perfect his papers up to the time of his death, and, as the invention was one of obvious importance, a bill was passed through Congress for the reopening of the case, and the patent was issued to the Graham heirs in 1878. Soon after the issue of the Graham patent, several extinguisher firms, viz, Charles T. Holloway, of Baltimore; W. K. Platt, of Philadelphia; S.F. Hayward of New York; the Protection Fire Annihilator Co., of New York; the Babcock Manufacturing Co., of Chicago, and the New England Fire Extinguisher Co., of Northampton, Mass., were licensed to manufacture under the patent, by Archibald Graham, as administrator of the estate of his father, who bound himself in these licenses to issue no other licenses except with the approval of all those who were included in the combination. This arrangement left several enterprising manufacturers out in the cold, and one of these, in investigating the status of extinguisher patents at Washington, discovered an assignment of a quarter interest of the Graham patent to a Mr. Burton, who, at the time of Graham's second application for a patent, had assisted him with $500. This assignment had long been forgotten--Burton having died, and his heirs knowing nothing of its existence. The widow of Burton was hunted up, an assignment was secured for $30,000, and a consolidated fire extinguisher company was formed, which became the owner of the one quarter interest in the patent. This combination, known as the "Fire Extinguisher Manufacturing Co.," included the Protective Annihilator Co., of New York; the Northampton Fire Extinguisher Co, of Northampton, Mass.; and the North American Fire Annihilator Co., of Philadelphia. The combination bought out the Babcock Co., who had already acquired the patents of the Champion Co., all the patents of the Conellies, of Pittsburg, and of the Great American Co., of Louisville, as well as the licenses of S. F. Hayward and W. K. Platt. This covers all the extinguisher patents in existence, except those of Charles T. Holloway, of Baltimore.
The advantages of the chemical engine are well summed up in the following statement:
The superiority of a chemical engine consists--
1st. In its simplicity. It dispenses with complex machinery, experienced engineers, reservoirs, and steam. Carbonic acid gas is both the working and extinguishing agent.
2d. In promptness. It is always ready. No steam to be raised, no fire to be kindled, no hose to be laid, and no large company to be mustered. The chemicals are kept in place, and the gas generated the instant wanted. In half the cases the time thus saved is a building saved. Five minutes at the right time are worth five hours a little later.
3d. In efficiency. Mere water inadequately applied feeds the fire, but carbonic acid gas never. Bulk for bulk, it is forty times as effective as water, the seventy gallons of the two smallest cylinders being equal to twenty-eight hundred gallons of water. Besides, it uses the only agent that will extinguish burning tar, oil, and other combustible fluids and vapors. One cylinder can be recharged while the other is working, thus keeping up a continuous stream.
4th. In convenience. Five or six men can draw it and manage it. Its small dimensions require but small area, either for work or storage. One hundred feet or more of its light, pliant hose can be carried on a man's arm up any number of stairs inside a building, or, if fire forbids, up a ladder outside.
5th. In saving from destruction by water what the fire has spared. It smothers, but does not deluge; the modicum of water used to give momentum to the gas is soon evaporated by the heat, doing little or no damage to what is below. This feature of the engine is of incalculable worth to housekeepers, merchants, and insurance companies.
6th. Economy. It costs only about half as much as a first class hand engine, and about one-fourth as much as a steam engine, with their necessary appendages, and the chemicals for each charge cost less than two dollars.
A correspondent ofEngineering Newssays: Those living on swift streams, and using small boats, often have occasion to tow up stream. So do surveyors, hunters campers, tourists, and others. One man can tow a boat against a swift current where five could not row.
Where there are two persons, the usual method is for one to waste his strength holding the boat off shore with a pole, while the other tows. Where but one person, he finds towing almost impossible, and when bottom too muddy for poling and current too swift for rowing, he makes sad progress.
The above cut shows how one man can easily tow alone. The light regulating string, B, passes from the stern of the boat to one hand of the person towing, T. The tow line, A, is attached a little in front of the center of the boat. Hence when B is slackened the boat approaches the shore, while a very slight pull on it turns the boat outward. The person towing glances back "ever and anon" to observe the boat's line of travel.
The following table, which has been prepared by the French Ministry of Public Works, gives the railway mileage of the various countries of Europe and the United States up to the end of last year, with the number of miles constructed in that year, and the population per mile: