OBJECTIVE
to develop a given angle using  angle gauges.
APPARATUS
angle gauges
petrolleum jelly/oil
cotton cloth

PROCEDURE
1) first of all we divide the given angle into no of angles whose sum is equal to the given angle and each of these angle is available as a standard angle gauge.
2) now we prepare the angle gauges to wrung together. for this purpose we first apply a little petroleum jelly tothe shiny sides of the angle gauge and then rub it off with cotton cloth. after this procedure a very less amount of the jelly remains on the surface which acts as an adhesive material and helps wrunging the angle gauges.
3) the angle gauges are weung together side by side to form the required dimension.
4) unlike the block gauges, angle gauges can be subtracted.