A text-book of geometrical drawing, for the use of mechanics and schools, in which the definitions and rules of geometry are familiarly explained .. (1850)
Minifie, William, 1805-1880. [from old catalog] · Baltimore, W. Minifie & co. · leaf 63
jFig. 5. … W:Mm^ PLATE X. ^^ I sides in the required polygon^ the quotient will be the angle atthe centre; for example;, let it be required to find the angle at thecentre of an octagon:—divide 360 by 8^ the number of sides^ thequotient will be 45^ which is the angle formed by the octagon at the centre. i 2nd.…
