Manual of Land Surveying

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. In a triangle having sides each one mile in length, the difference in area, whether it be regarded as a plane triangle, or a triangle having sides curved with the earth's surface, is only 2} square feet. Each of the angles of such a spherical triangle would only exceed that Of the plane triangle by o.0019. And the angles Of a spherical triangle, whose area is square miles, would only exceed those of the plane triangle, having sides of the same length, by I.