Inclined Measure.

b=asin. Bsin. A,c=asin. Csin. A.

b=asin. Bsin. A,c=asin. Csin. A.

To compute the Areas of Triangles.—When two sides and the included angle are known,aandbrepresenting the two sides and θ the included angle,

A =a bsin. θ2.

A =a bsin. θ2.

To find by logarithms the area in acres and decimals of an acre,

Log. A = log.a+ log.b+ log. sin. θ - 15·30103.

Log. A = log.a+ log.b+ log. sin. θ - 15·30103.

When two angles and the included side are known, β and θ being the angles andathe included side,

A =a2sin. β sin. θ2 sin. (β + θ).

A =a2sin. β sin. θ2 sin. (β + θ).

To find by logarithms the area in acres and decimals of an acre,

Log. A = 2 log.a+ log. sin. β + log. sin. θ - log. sin. (β + θ) - 15·30103.

Log. A = 2 log.a+ log. sin. β + log. sin. θ - log. sin. (β + θ) - 15·30103.

When the three sides are known,abcbeing the three sides andstheir half sum,

A = √s(s-a)(s-b)(s-c).

A = √s(s-a)(s-b)(s-c).

To find by logarithms the area in acres and decimals of an acre,

Log. A =log.s+ log. (s-a) + log. (s-b) + log. (s-c)2- 5.

Log. A =log.s+ log. (s-a) + log. (s-b) + log. (s-c)2- 5.

Table showing the Reduction in Links and Decimals of a Link to be made per Chain for every Half Degree of Inclination from 3° to 30°.

Table showing the Reduction in Links and Decimals of a Link to be made per Chain for every Half Degree of Inclination from 3° to 30°.

Table of Corrections in Feet and Decimals of a Foot.

Table of Corrections in Feet and Decimals of a Foot.


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