A Practical Theory of Voussoir Arches

a₁ abutment angle of friction apex arch balanced arch ring b₁ beam Bland's Brevet bricks bridge centre of gravity centre of pressure cloth column components compressibility construction contour curves corresponding crown joint curve of pressures depth of joint depth of keystone direction drawing edge of joint edge of pier edition engravings experiments extrados form of arch formulæ Gothic arch hence horizontal force horizontal thrust Hypsometry Illustrated inner edge inner third intrados Iron joints of rupture line of pressures lower edge method middle third minimum mortar NOSTRAND'S PUBLICATIONS outer edge P₁ P₂ pass a curve plates point of application practice pressures passes R₁ rafter resultant revised and enlarged rolling load Scheffler sliding span spandrel springing joint stability Steam Engine stone sultant summit suppose surface symmetrical Telegraphy theory thick tical tion Treatise U. S. Navy vertical voussoir arch weight wood cuts