The regular work of cultivation of garden and experimental plots should be carefully attended to. Pupils in this Form should be able to do all kinds of garden work with a good deal of proficiency. The work of selecting the best flowers for seed production should be continued. These should be used for planting in the school garden and in home gardens as well. This part of the work might be left to the girls. The boys should be encouraged to take up the systematic selection of seed grain. To get good seed to start with, two methods may be used:
1. Decide upon the kind of grain to be selected and choose from one of the best fields a hundred of the best heads—those that are vigorous, clean, free from rust or smut, and standing up straight. When the heads are dried a little, shell the grain off them and preserve it in a jar in a cold, dry place until spring.
2. Take a quart of oats and pick it carefully, keeping only the largest and most plump kernels. Keep this for spring planting. At the same time, a sample of the poorer grains should be kept for comparison. A regular system of selection should be followed from year to year, taking enough of the largest, brightest, and most compact heads from the plot each autumn to sow a plot of equal size the next spring. After the selection of heads has been made,the remainder of the crop may be harvested, and the grain from this known as general crop from hand-selected seed of the first, second, third year, etc. If the value per acre is required, the plots should be made of a certain size easy to compute, such as one rod square or one rod by two rods. (10-1/2 ft. by 21 ft. is about 1/200 acre.) Samples of each crop should be kept in uniform bottles and labelled; for example—"From selected heads of 1911". The yield per acre in the plot from which the selected heads came should also be noted. These will be interesting for purposes of comparison and for testing duration of vitality later. If the same amount of grain is used in planting a plot each time, the change in bushels per acre may be ascertained and also in pounds per bushel. Some of the boys in this Form may wish to continue this work of improvement by selection and, if so, they should communicate with the Secretary of the Canadian Seed Growers' Association, Canadian Building, Ottawa, and receive full instructions to enable them to carry on their work practically as well as scientifically.
The teacher should encourage the growing of herbaceous perennials for the purpose of beautifying the school grounds. Many plants may be started from seed at the school and given to the pupils for home planting. These plants require but little attention and provide excellent bloom in gardens and home grounds from early in spring before annuals are in bloom, on into the autumn. A list of the best varieties will be found in Circular 13, onElementary Agriculture and Horticulture, a copy of which should be in every school. The seed plot should be fertilized and prepared in the usual way, and the seedsplanted before the first of September. They may be started in June also, in which case they make more growth before winter. The plot should be well fertilized with thoroughly rotted manure and, if the soil is very dry, the plot should be well watered the day before the seeds are planted. The seeds are usually quite small and should be covered very lightly. The plot should be protected from the hot sun by means of cheese-cloth tacked on a frame. The plants should be watered twice a week in dry weather. In the late autumn, when the ground freezes, the plot should be covered with leaves or straw and some boards, which should be removed when the frost comes out in the spring.
Before the pupils of this Form leave school they should be able to recognize, by name as well as by sight, all of the species of trees found in their vicinity. To this end the teacher should help them to prepare an inventory of species of trees, shrubs, and vines of the vicinity. They should learn to distinguish the different species of maples, elms, birches, etc. A named collection of leaves helps materially in doing this. The influence of environment upon the growth and shape of trees and how trees adapt themselves to the conditions in which they live is a most interesting and profitable study, demanding careful observation, reflection, and judgment.
Muldrew:Sylvan Ontario.Briggs.
Keeler:Our Native Trees.Scribners' Sons. $2.00.
Consider the influences at work and their effect under the following heads:
1.Character of the Soil and Subsoil.—It may be gravelly, pure sand, sandy loam, clay or clay loam, muck or humus, shallow or rocky, and the subsoil may be sand, clay or hard clay with stones (hard-pan). Notice what species are most common in each kind of soil.
2.Water Supply.—What species are found naturally in moist ravines or along the margins of rivers and lakes, in bogs or swamps, on dry, sandy plains, or rocky hillsides. Consider also the rainfall.
3.Exposure to Sunlight.—Account for the lack of symmetry in the shapes of trees. Branches grow only where their leaves can get the light. Account for the pith in many tree stems not being in the geometric centre. Account for the rapid growth in height made by young trees in the woods. Their light supply is chiefly from above, and they stretch up toward it as rapidly as possible. Dim light causes rapid growth at the expense, however, of strength of tissue, but as these young trees are protected in the woods from the strain of wind storms, their slimness and lack of toughness is a benefit rather than a hindrance to them. Also, the limbs near the ground die off while the trees are still young and small, giving us the clear timber tree, free from large knots, tall and straight. Make further application of this principle of light in relation to the planting of trees for shade and for wood or lumber. Account for the large size of the leaves of young trees in the dimly lighted woods as compared with the leaves of older trees. The principle of rapid growth in dim light is seen here also. It will be noticedthat the large leaves of the young trees are more thin, soft, and flexible.
4.Wind.—Observe the tops of tall trees that have always been exposed to a strong prevailing wind as, for instance, those growing on the tops of hills or the eastern shore of a lake which has a prevailing west wind. The tops lean in the direction in which the prevailing wind blows. Does strong wind help or hinder the growth of a tree? Examples of stunted trees on wind swept hills or shores readily show this. It will be seen also that the higher branches are poorest on the side most exposed to the wind.
5.Suitability of the Species to the Climate.—Observe that some trees retain their leaves much later in the autumn than do others. The beech, hickory, red oak, and chestnut are good examples. These are on the northern extreme of their territory of growth. The tree best suited to a rigorous climate is the one that finishes its work early in the autumn and has all its tissues well matured before cold weather sets in. Examples: maple, elm, birch, and willow.
If the teacher can arrange to take the pupils to see a well-kept orchard about the time of the apple harvest, it will help to arouse interest in the study of fruits. The trees, as well as the fruit, frequently show distinguishing marks whereby they may be identified. Have the pupils notice the following points: general shape of tree, colour of bark, shape of leaf, method of cultivation, fertilizing, pruning and grafting, spraying and its need, orchard pests, method of picking and packing apples in barrels and boxes for market.
Study the method of propagating strawberries and such bush fruits as currants, gooseberries, raspberries, and blackberries. Reports issued from the Fruit Division of the Experimental Farm at Ottawa give information regarding the best varieties suitable for different parts of Ontario and Quebec. Have the pupils try propagating strawberries by taking the stolons or runners; currants and gooseberries, by means of layers or stem cuttings; and raspberries or blackberries, by root cuttings or the detaching of root shoots or suckers. Stem and root cuttings, when taken in the autumn, may be planted at once or may be stored in damp moss or sand in a cold cellar over winter. Stem cuttings should be about the size and length of a lead-pencil and root cuttings about half that size.
Observations made with garden flowers should be supplemented by observation lessons on a few selected wild flowers of the woods, fields, and roadsides. Although the spring months afford a much greater variety of wild flowers than do the autumn months, they do not afford quite as good an opportunity for finding and studying them. The woods and fields are drier and more easily reached in the autumn and the fall flowers last much longer. Some of the species seen blooming in spring and early summer are now in fruit and scattering their seed, so that the pupils have a chance to follow out the whole life history of a few chosen species. The pupils in this Form might select for special study the milkweed, worm-seed mustard, wild aster, and goldenrod. These should be observed out-of-doors, preferably, but suitable class-room lessons may be taught by using similar matter.
Taking the milkweed as a type, the following points are to be considered:
The kind of soil, where found, and whether in sun or shade.
Try to pull up a small-sized plant. Dig one up and notice the underground part.
Note the size of the largest plant seen, also the size of the leaves, and how they are arranged to prevent overshadowing.
Break off a leaf and note the white sticky juice, whence the name "milkweed". Discuss this milk as a protection to the plant.
Note time of first and last flowering of the plant and the colour and odour of the flowers. Watch insects gathering honey on a bright day. Note the little sacks of pollen that cling to their feet. They sometimes get their feet caught in little slits in the flower and perish.
After the flowers disappear, note the forming of the little boat-shaped pods in pairs. Select one that is ripe and notice that it bursts along one side which is most protected. Open a pod carefully and notice how beautifully the flat, brown seeds are arranged in overlapping rows and how each seed has a large tuft of silky down that serves to carry it far away in the wind. This silk-like down is sometimes used to stuff cushions, and because of it the plant is sometimes called silk weed.
One species of butterfly in particular feeds upon this plant—the monarch, or milkweed, butterfly. This is one of the few butterflies that birds do not eat. It is protected by a distasteful fluid. Look on the under side of the leaves of several plants until you find a pretty, pale green cocoon with golden dots, hanging by a thread-likeattachment. Early in the season the larvæ may be found feeding on the leaves.
This plant is troublesome in some fields and gardens and so is classed as a weed. When the stems come up in the spring, they are soft and tender and are sometimes used as pot herbs.
Draw a leaf, a flower, a pair of pods, and a seed with its tuft.
Write an account of a visit to the woods to study wild flowers.
A study of the pines of the locality may be commenced in November, after the deciduous trees have lost their leaves and have entered their quiescent winter period. This is the time when the evergreens stand out prominently on the landscape, in sharp contrast with the other trees that have been stripped of their broad leaves and now look bare and lifeless. If no pines are to be found in the vicinity, cedar or hemlock may be substituted. The lessons should, as far as possible, be observational. The pupils should be encouraged to make observations for themselves out of school. At least one lesson should be conducted out-of-doors, a suitable pine tree having been selected beforehand for the purpose. The following method will serve as a guide in the outdoor study of any species of tree:
Have the pupils observe the shape and height of the tree from a distance and trace the outline with the finger. Compare the shape of this tree with others near by of the same species and then with members of other species.Have the pupils describe in what particulars the shapes differ in different trees. They will come to realize that the difference in shape results from differences in length, direction, and arrangement of branches. They may notice that other evergreens resemble the pine in that the stems are all straight and extend as a gradually tapering shaft from the bottom to the top, that all have a more or less conical shape, and that the branches grow straight out from the main stem and not slanting off as in the case of the maples and elms.
Coming close to the tree, the pupils may first examine the trunk. By using a string or tape-line, they may find out how big it is around and the length of the diameter. Tell them how big some evergreens are (the giant trees of the Pacific Coast are sometimes over forty feet around). Have them notice where the trunk is largest, and let them find out why a tree needs to be so strong at the ground. Heavy wind puts a great strain on it just at this point. Illustrate by driving a long slat or lath into the ground firmly: then catching it by the top, push it over, and it will break off just at the ground. If a little pine tree could be taken up, the pupils would be interested in seeing what long, strong, fibrous roots the pine has.
Let them examine the bark of the trunk and describe its colour and roughness. The fissures in the bark, which are caused by the enlarging of the tree through the formation of new wood under the bark, are deeper at the bottom of the tree than at the top—the tree being younger and the bark thinner, the nearer to the top we go. How old is the very top, down to the first whorl of branches? How old is the stem between the first and second whorls? Between the third and fourth? Let the pupils find out in this way the age of a little pine that is regular and unbroken. Thewhorls of branches near the ground are usually small and dead in young trees and in old trees have completely disappeared. Relate the size of the trunk to its age, and also relate the size and length of the branches to their age. Where are the youngest branches and how old are they? What branches are oldest? Notice how the branch is noticeably larger just where it joins the trunk, as this is the point of greatest strain. Are the branches the same length on all sides of the trunk? If not, find one where branches are shorter on one side than on the other and try to discover the cause. Usually, if other trees are near enough to shade a certain tree, the branches are shorter and smaller on the shaded side.
Let the pupils look up into the tree from beneath and then go a little distance away and look at it. They will notice how bare the branches are on the inside, and the teacher will probably have to explain why this is so. They will discover that the leaves are nearly all out toward the ends of the branches. The leaves get light there while the centre of the tree top is shaded, and the great question that every tree must try to solve is how to get most light for its leaves. The pupils will now see an additional reason why the lower limbs should be longer than the upper ones. The greater length of the lower limbs brings the leaves out into the sunlight.
Why this tree is called an evergreen may now be considered. Why it retains its leaves all winter is a problem for more advanced classes, but if the question is asked, the teacher may get over the difficulty by explaining to the class that the leaves are so small and yet so hardy that wind and frost and snow do not injure them.
The pupils may each bring a small branch of twig back to the school-room, if the white pine is growing commonlyabout, otherwise the teacher may provide himself with a branch upon which to base another observation lesson in the class-room.
If the tree has cones on it, an effort should be made to get a few, as they will also be considered in a subsequent class-room lesson. If the cones have not yet opened when they are picked, so much the better, as they will soon open in a warm room, and the pupils will be able to examine the seeds and notice how they whirl through the air in falling. If possible, let the pupils have an opportunity of seeing pine trees growing in the woods as well as in the open.
Inferences.—If possible, each pupil is supplied with a small branch of the white pine and the teacher with a larger branch which can easily be seen by all the pupils. Before proceeding to examine the specimens, give the pupils a chance to tell what they now know about the white pine, and thus review the lesson taken out-of-doors. Then ask a few questions bearing upon their own observations, such as: What was the soil like where you found the pine tree growing? (They are found most commonly on light, sandy soil.) Did you notice any difference between the shapes of the pines in the deep woods and the pines in the open fields? Did you notice any dead limbs on those in the woods? Why did they die? The pupils may conclude that branches whose leaves cannot get the sunlight must die. Show that this causes knots in the lumber and exhibit samples. This explains also why the trees of the forest have such tall stems without branches for a long distance up from the ground. They get the light only from above and seem to strive with the surroundingtrees to reach it. If we want trees to grow tall, how should we plant them? (Close together) What would such trees be good for? (Making timber or lumber) If we want trees to grow low and have thick and bushy tops, how should we plant them? (Far apart) What would such trees be good for? (Their shade and their beauty) Good shade trees should be thirty to forty feet apart.
Ask the pupils if they have ever been near a pine tree when a gentle breeze was blowing, and have them tell the cause of the sound that they heard. They may decide that the shape and size of the leaves caused the sound when the wind was blowing through the tree top. Have them examine the branches in order to discover the following points:
Leaves.—These are in bunches of five, two to three inches long, three-cornered, and with little teeth pointing toward the tip, light green near the tip of the bough (young leaves) and darker further down (older leaves); age of a leaf the same as the age of the wood it grows on, therefore some leaves are one year, some two, and a few three years old. No leaves on four-year-old wood, therefore the leaves fall off the white pine the third year. Ask pupils to try to find out by observation when the leaves fall off the pines. Note the fragrance of the leaves, and that they are sometimes put into "pine" cushions, also, how slippery they are to walk on.
Buds.—These are found at the tips of the branches, one large one in the centre and several smaller ones grouped around it. Note their reddish-brown colour and that they are made up of scales overlapping and covered with gum which keeps out the rain, thus protecting the little growing tip inside. When buds grow, they become little twigs with leaves on. Find where the buds were a year ago.Notice the light colour of the twigs that grow during the present season and the darker colour of the twigs of the previous year. Where were the buds two years ago? What did the centre bud become? (A continuation of the stem) What did the other buds, called lateral buds, become? (New branches) Compare the growth made in different years.
Notice also how white the wood of the twigs is—the probable reason for calling it "white pine".
Cones.—Note the length and shape of the cones and how the seeds are placed in them inside the large scales. Get some of the seeds and note the wing-like attachment. Take the wing off a seed and drop it from a height at the same instant with one that has its wing attached. Note the whirling motion and infer what purpose the wing serves in scattering seed. Taste the kernel of a pine seed and discover why squirrels are fond of them. Burn a pine cone.
Find out what birds like to live in this tree. What has been noticed about them and their nests?
Have the pupils keep the seeds until the following spring by putting them in a box of dry sand and setting them in a cold place. They should then plant them in a corner where they can be partly shaded when the sun is bright. Plant them about half an inch deep and keep them watered if the weather is dry during the first summer.
Note.—The cones drop their seeds from high up in the tree so that the wind can carry the seeds long distances. The cones usually stay on the trees for a couple of years after they lose their seeds.
Draw a pine tree, a bunch of pine needles, a pine cone, and a pine seed.
Write a description of a pine tree seen in the woods; also of one found in the open.
Write a list of things for which the white pine is useful.
To the teacher.—The winter months, besides affording an opportunity for seeing trees and plants in their dormant or quiescent condition, also afford an opportunity for reading and reflection, for recalling observations and experiences of the past season, and for making plans for work and study in the school garden, woods, and fields when spring returns. The knowledge gained by the pupils through first-hand observation of trees, flowers, and gardens can be greatly extended by pictures and stories descriptive of these, which the teacher may from time to time bring to the school-room. Their personal experiences will be the basis for interpretation of many new things which will come up in the reading lessons, in selections which the teacher reads from week to week, and in books and papers which they themselves read in their homes. Thus the interest that is aroused by the first-hand studies of plants in garden, orchard, or woodland will be carried over from autumn to spring, and the pupils, with the awakening of spring, will take up anew the study of plant life with a keener interest because of the time given to reading and reflection during the winter. Illustrated magazines dealing with gardening and with the study of trees and plants, and such magazines as have a children's department, will prove of great assistance to the teacher who makes any serious attempt to interest pupils in plant studies. Stories of life in the woods and of plant studies suitable to young pupils should be used.
Margaret Morley:Flowers and their Friends.Ginn & Co. 50 cents.
Margaret Morley:Seed Babies.Ginn & Co. 25 cents.
Margaret Morley:Little Wanderers.Ginn & Co. 30 cents.
Alice Lounsberry:The Garden Book for Young People.Stokes. $1.50.
Gertrude Stone:Trees in Prose and Poetry.Ginn & Co. 45 cents.
Discuss the names, keeping and cooking qualities of the apples, and bearing qualities of the trees.
Provide each member of the class with a typical representative of each of the above varieties of apples.
Compare the three apples as to size, form, colour—including marks; hardness, length, and thickness of stem; depth of cavity at the stem end; depth and shape of the cavity at the calyx end.
Split each apple from stem to calyx and compare as to the thickness and toughness of the skin, the colour of the flesh, the size of the core, taste and juiciness of the flesh.
To the teacher.—All three are apples of fair size, the Baldwin being on the average the smallest of the three. All three are roundish, but the King is somewhat oval-round, and the Spy, conical-round. The Baldwin has a yellowish skin with crimson and red splashes dotted with russet spots. The King is reddish, shading to dark crimson. The Spy has a yellowish-green skin sprinkled with pink and striped with red.
The beautiful colours make all these apples very popular in the markets of American cities and in those of the British Isles; but the soft and easily damaged skin of the Spy makes it the least desirable as an apple for export.
All keep well and in cool cellars remain in good condition until April. They may be kept much longer in cold storage chambers, where the temperature is uniformly near the freezing point of the apple.
The Baldwin apple tree is reasonably hardy within the ordinary range for apple trees, and its yield is a satisfactory average. The King apple tree is not a hardy tree, nor is it a satisfactory bearer except in the best apple districts. The Spy is a fairly hardy tree and thrives and yields well throughout a wide range; but it does not begin to bear until it is about fifteen years old.
A comparative lesson may also be based on selected varieties of autumn apples, such as Fameuse, McIntosh Red, Wealthy, Gravenstein, and St. Lawrence.
Begin the study of the codling moth in August by examining wormy apples. Find out, by asking the pupils, which orchards of the locality had been sprayed in the spring.
Ask the pupils to count out at random one hundred apples and to select from these the number that are wormy. What percentage of the apples are wormy? Compare the percentage of wormy apples in unsprayed, with that in sprayed, orchards. The results will afford evidence of the benefit of spraying.
Find out, if possible, the dates on which, and the conditions under which, the spraying of the orchards with the least number of wormy apples was done.
Ask the pupils to bring to the school-room a number of wormy apples. Have the pupils cut these open and note the nature and position of the hole, or burrow, and the amount of damage done to the apples.
Have the pupils observe the larva and note the size, colour, shape, and number of legs.
To the teacher.—The apple maggot is a less common insect larva and may be distinguished from the larva of the codling moth by the fact that the former has no legs and has the habit of burrowing in all directions through the pulp of the apple, while the larva of the codling moth works almost entirely in the core.
The cocoon and pupa phase of this insect may be obtained by keeping the wormy apples in a box containing loose paper on which the cocoons will be placed, or by searching under the bark scales of apple trees in October.
Describe the cocoons. Open some of them and describe the contents. Keep the remaining cocoons in a box or vivarium in a cool place during the winter.
What birds are seen tapping at the bark scales of the apple trees during winter? Examine the bark scales when a downy woodpecker has been at work and note that the cocoons have been destroyed.
Should we encourage the visits of woodpeckers to the orchards?
By hanging up a beef bone in the orchard, various birds, including woodpeckers, will be induced to visit and perhaps to make their homes in the orchard.
Common Insects Affecting Fruit Trees, Bulletin No. 158, Department of Agriculture, Parliament Buildings, Toronto.
Bulletins Nos. 158 and 171, Ontario Department of Agriculture, deal with many insect pests and their remedies.
In May look for the adult moths as they emerge from the cocoons. Observe the colour, size, shape, and the bright copper-coloured horse-shoe on the front wing—the "brand" of the codling moth.
Examine the little apples when the blossoms are falling. Note the tiny, flat, oval-shaped egg at various places on the surfaces of the apples and a few days later the tiny worm which emerges from the egg. This soon eats its way into the apple, entering usually at the calyx end. If spraying is done after the petals have fallen and just before the calyx end closes up, a drop of poison is inclosed, and when the larva enters it and begins eating its way into the apple, it gets the poison.
Brief lessons should be given on some of the lower members of the animal kingdom, for the purpose of broadening the interests of the pupils. The following are suggested as types: snail, spider, freshwater mussel (clam), crayfish (crab), centiped, milliped, salamander, and wood-louse.
These are common animal forms, most of which are frequently seen by the pupils, but seldom are their interesting life habits or their places in the animal kingdom recognized. The salamander is to many pupils a lizard of the most poisonous kind; centipeds and millipeds are worms, and they do not recognize that the clam is an animal with sensibilities and instincts.
Kellogg:Elementary Zoology
Silcox and Stevenson:Modern Nature Study
Under stones and sticks in moist soil are to be found two worm-like forms, both having many legs.
One of these animals is flat, about an inch long, brown in colour, and provided with a pair of long feelers. On each division of the body is a single pair of legs. This is thecentiped. The other animal is more cylindrical in shape and has two pairs of legs on each division of the body. Its colour is a darker brown than that of the centiped, and it has a habit of coiling into a spiral shape, when disturbed, so that the soft under surface is concealed. This is themilliped. Both of these animals are quite harmless and feed on decaying vegetable matter. They stand midway between worms and insects in forms and habits.
A brief observation lesson on each animal, involving their movements and the structural features named above, will enable the pupils to identify them and to appreciate their position in the animal kingdom.
Some forms of these are found in water, as in streams, ponds, and ditches, while other forms are found on land, where they hide under stones and sticks. They are commonly mistaken for lizards, which they closely resemble in shape; but the two animals may be distinguished by the fact that the surface of the body of a salamander is smooth, while that of a lizard is covered with scales.
The small red or copper-coloured newts are the most common in Ontario and are frequently found on roads after heavy rains. The tiger salamanders are larger than the red newts and are marked with orange and blackspots, hence the name "tiger". Many people believe this species to be especially venomous, while in reality it is quite harmless and, like the other salamanders, is useful for destroying insects and small snails, which form the greater part of its food.
To the teacher.—The superstition of the salamander's power to extinguish a fire into which it is thrown still exists. The early life of the salamander is spent in water, the young form being very much like a tadpole. The salamanders are close relatives of the frogs and toads and may be kept in a jar or vivarium in wet moss or grass. The pupils should learn to recognize the animals and should be instructed as to their habits.
Problems in observation.—In how many places can you find spiders' webs? How many forms of spiders' webs can you find? Are the many webs that are found on the meadow grass in the dewy mornings the homes of spiders? If so, describe where the spiders live. (At the bottom of tunnels that run into the ground.)
What uses do spiders make of their webs? (Trapping prey, supporting egg cases, protection, and means of moving, as in the case of cobweb spiders.)
Drop a fly upon a spider's web and observe the action of the spider. Search under the webs of spiders in attics and sheds and learn, from the skeletons found there, what the spider feeds upon. It will be found that flies, beetles, and other spiders are killed by this monster.
Watch a spider spinning its web and find out what parts of the body are used in this work. It will be seen that the threads are produced from little tubes at the rearend of the animal and are placed and fastened by means of the feet.
Examine, by the aid of a hand lens, the feet and head of the spider. Note the "brushes and combs" on the former. Note, on the latter, the four, six, or eight eyes (the number and arrangement vary), and the short poison claws at the front of the head. How are the poison claws adapted for seizing and piercing? Note the sharp hooks at the lower ends.
Continue the lessons in bird identification and in bird types, using the methods outlined for these studies in Form III. (See pp. 217-24.)
Several species of evergreens have already been studied. These should be reviewed, and representatives of other species examined. Mid-winter is most suitable for the study of evergreens. The following points should be considered:
1. Description leading to identification
2. Nature of soil and water conditions
3. Common uses of each species of evergreen
4. Collection of wood specimens and cones.
Specimens should be uniform in size and should show bark on one side and heart wood as well as the outside, or sap wood. They should be about six inches long, two inches wide on the side having the bark, and should gradually come to an edge toward the pith, or centre. When seasoned, one side and one edge should be polished and then oiled or varnished. Specimens of the wood of the deciduous trees may also be prepared during the winter.
During the winter months, some time should be devoted to reading and discussing articles on general farming and fruit growing. Such articles may be taken from books, magazines, or newspapers, and may be supplied partly by the teacher and partly by the pupils. These articles will be appreciated by the pupils all the more because of their studies of fruit trees during the season. Such topics as the following may be discussed:
1. Best kind of apples, plums, bush fruits, and strawberries. Reports from the Dominion and Provincial Departments of Agriculture.
2. Method of raising fruit trees—from seed, grafting, and budding.
3. Demonstrations in pruning. This may be done in early spring by taking a class to a neighbouring orchard.
4. Methods of planting and cultivation.
5. Packing and storing.
6. Spraying. Much information is to be found in Horticultural Journals and papers, and in Bulletins to be obtained from the Secretary of Agriculture for Ontario.
Illustrated articles on gardening and fruit growing should be collected for school use. Views of fine gardens, parks, and home grounds will be of interest to the pupils. Simple artistic methods of ornamental planting with trees, shrubs, vines, and herbaceous perennials can now be introduced, and some scheme for improving the school grounds outlined.
Catalogues should be obtained soon after New Year's and, after examining their merits, the best varieties of seed and fruit for the district should be selected. Horticulturalsocieties, as well as Dominion and Provincial Departments of Agriculture, commonly give selected lists with descriptions of the different varieties.
The training in the observation and identification of weeds and weed seeds, which was begun in Form III, should be continued in Form IV. For method see Form III.
1. Grasp an empty tin can by the top and push it down into a pail of water. Note the tendency of the can to rise. The water presses upward. Its downward pressure is evident.
2. Tie a large stone to a string, hold it at arm's length, shut the eyes, and lower the stone into water.Notethe decrease in weight. This is also due to upward pressure, which we call buoyancy. The actual decrease may be found by means of a spring balance.
3. Try Experiment 2, using a piece of iron the same weight as the stone. Is the decrease in weight as evident? Ships made wholly of iron will sink. Explain.
4. Put an egg into water; it slowly sinks. Add salt to the water; the egg floats.
1. Will the human body sink in water? In which is there less danger of drowning, lake or sea water?
2. When in bathing, immerse nearly the whole body, then take a full inspiration. Note the rise of the body.
3. Why does ice float? (See expansion of water by freezing.)
4. Balloons are bags filled with some light gas, generally hydrogen or hot air. They are pushed up by the buoyancy of the air. The rise of heated air or water (see Convection) is really due to the same force. Clouds, feathers, and thistledown are kept in the air more by the action of winds and small air currents than by buoyancy.
(ConsultScience of Common Life, Chaps. VIII, IX, X.)
(ConsultScience of Common Life, Chaps. VIII, IX, X.)
1. Air takes up space. Put a cork with one hole into the neck of a flask or bottle. Insert the stem of a funnel and try to pour in water. Try with two holes in the cork. When we call a bottle "empty" what is in it?
2. Air is all around us. Feel it; wave the hands through it; run through it; note that the wind is air; inhale the air and watch the chest.
3. Air has weight. This is not easy to demonstrate without an air-pump and a fairly delicate balance.
Fit a large glass flask with a tightly fitting rubber stopper having a short glass tube passing through it. To the glass tube attach a short rubber one and on this put a clamp. Open the clamp and suck out all the air possible. Close the clamp and weigh the flask. When perfectly balanced, open the clamp and let the air enter again. Note the increase in weight.
If an air-pump is available, procure a glass globe provided with a stop-cock (see Apparatus). Pump some of the air from the globe, then weigh and, while it is on the balance, admit the air again and note increase in weight.
Tie a piece of thin sheet rubber over the large end of a thistle tube; suck the air out of the tube and note how the rubber is pushed in. This is due to the weight or pressure of the air. Turn the tube in various positions to show that the pressure comes from all directions. To show that "suction" is not a force, let a pupil try to suck water out of a flask when there is only one opening through the stopper. If two holes are made, the water may be sucked up, that is,pushedup by the weight of the air.
Fill a pickle jar with water. Place a piece of writing paper on the top and then, holding the paper with the palm of the hand, invert the jar. The pressure of the air keeps the water in.
A cubic foot of air weighs nearly 1-1/4 oz. Find the weight of the air in your school-room.
The atmosphere exerts about fifteen pounds pressure on every square inch of the surface it rests against. Find the weight supported by the top of a desk 18 inches by 24 inches. If the surface of the body is eight square feet, what weight does it have to sustain? Why does this weight not crush us?
The experiments immediately preceding will have paved the way for a study of the barometer.
1. Fill a jar with water and invert it, keeping its mouth below the surface of the water in another vessel. If the pupils can be led to see that the water is sustained in the jar by the air pressing on the water in the vessel, they can understand the barometer.
2. Fill a tube about 30 inches long, and 1/4 inch inside diameter with water, and invert it over water, as with the jar in the previous experiment.
3. Use the same tube or one similar to that in 2 above, but fill with mercury and allow the pupils to notice the great weight of the mercury. Holding the mercury in with your finger, invert the tube over mercury. This time the fluid falls some distance in the tube as soon as the finger is removed. A tube of this size requires 1 lb. of mercury.
Lead the pupils to see that the mercury remaining in the tube is sustained by the air pressure, and that any increase or decrease of the atmospheric pressure will result in the rise or fall of the mercury column. Leave the barometer (made as in 3 above) in the room for a few days and note whether its weight changes. The use of the instrument in predicting weather changes should be emphasized. Compare your barometer with the records in the daily papers.
The average height of the barometric column is 30 inches at sea-level. Explain how you could estimate heights of mountains and balloons with a barometer.
This is a valuable application of air pressure. A glass model will prove useful, but a model made by pupils will be much more so. (SeeLaboratory Exercises in Physicsby Newman.)
The water rises in the pump because the sucker lifts the air from the water inside, allowing the air outside to push the water up. A common pump will not lift water more than about 30 feet. Why is this? Compare the pump to a barometer. (SeeThe Ontario High School Physics.)
Air and all other gases manifest a pressure in all directions not due to their weight. The power of air to keeptires and footballs inflated and that of steam in driving an engine are examples. It is this force that prevents the pressure of air from crushing in, since there are many air spaces distributed throughout the body.
This subject and the three immediately following it have a special bearing on hygiene.
1. Invert a sealing-jar over a lighted candle. Has the candle used upallthe air when it goes out?
2. Place a very short candle on a thin piece of cork afloat on water in a plate; light the candle, and again invert the jar over it. Note that the candle goes out and the water rises only a short distance in the jar; thereforeallthe air has not been used up.
3. Slip the glass top of the jar under the open end and set the jar mouth upward on the table without allowing any water to escape. Now plunge a lighted splinter into the jar. The flame is extinguished.
Air, therefore, contains an active part that helps the candle to burn and an inactive part that extinguishes flame. The namesoxygenandnitrogenmay be given. These gases occur in air in the proportion of about 1:4. (This method is not above criticism. Its advantage for young pupils lies in its simplicity.)
Make two or three jars of oxygen, using potassium chlorate and manganese dioxide. (See any Chemistry text-book.) Let the pupils examine the chemicals, learn their names, and know where to obtain them. Perform the following experiments:
1. A glowing splinter relights and burns very brightly if plunged into oxygen.
2. A piece of picture wire tipped with sulphur burns with great brightness.
3. Burn phosphorus or match heads in a spoon. A spoon may be made by attaching to a wire a bit of crayon having a hollow scooped on its upper surface. A clay pipe bowl attached to a wire will answer.
From these experiments pupils will learn the value of nitrogen as a diluent of the oxygen. Pure oxygen entering the lungs would be just as destructive as it would be entering the furnace.
1. Make a jar of this gas. Washing soda and vinegar will answer if hydrochloric acid and marble are not obtainable. (Consult theScience of Common Life, Chap. XIII, and any Chemistry text-book.)
2. Lower a lighted candle first into a jar of air then into the jar of carbon dioxide.
3. Make some lime-water by stirring slaked lime with water and allowing the mixture to settle. Shake up some clear lime-water with a jar of the gas. Pupils will be made to understand that the milky colour will in future be considered the test for carbon dioxide.
4. Have one of the pupils cause his breath to bubble through some clear lime-water for a minute. Using a bicycle pump, cause some fresh air to bubble through lime-water.
5. Hold a clear jar inverted over the candle flame for a few seconds, then test with lime-water.
6. Invert a large jar over a leafy plant for a day. Keep in the dark and test the jar with lime-water.
Is this gas likely to be in the air? Set a plate of lime-water in the school-room for a day or two, and then examine it. Try to pour the gas from jar to jar and use a candle as a test. Is the gas heavier than air?
On account of its weight, the gas often collects in the bottoms of old wells, mines, and tunnels. It is dangerous there since it will not support life.
Uses:
1. Add a little water to some baking powder and cause the gas that forms to pass through lime-water. What causes the biscuits to "rise"?
2. Mix flour and water in a jar, add a bit of yeast cake and a little sugar, and let stand in a warm place. Test the gas that forms, for carbon dioxide. What causes bread to rise?
3. Uncork a bottle of ginger ale, shake the bottle, and lead the gas that comes off through lime-water.
4. Most portable fire extinguishers depend on the generation of carbon dioxide.
Show the similarity between our bodies and the candle. The candle needs oxygen; it produces heat, and yields water and carbon dioxide. Much of our food is somewhat similar in composition to the wax of a candle; we breathe oxygen, our bodies are warmed by a real burning within, and we exhale water and carbon dioxide.
After exercise why do we feel more hungry? Why do we breathe faster? Why do we feel warmer? Why does the fire burn better when the damper is opened?
All air contains carbon dioxide. If the amount exceeds 6 parts in 10,000, it becomes an impurity, not somuch on its own account as because it indicates a poisoned state of the air in a room, since organic poisons always accompany it when it is emitted from the lungs.
Other impurities of the air, dependent on the locality and the season, are smoke, dust, disease germs, sewer gas, coal-gas, pollen dust.