By simple promotion and remotion, assisted by some flexure and extension, the distal spines of each would reach and scratch the substratum and, on remotion, sweep coarse particles posteriorly and dorsally.

The use of gun-cotton proper (trinitrocellulose) could not be thought of, owing to the brisant action of this body, but it was found that collodion-wool (dinitrocellulose, soluble gun-cotton), which was less brisant, could be converted into a nearly homogeneous mass which satisfied many of the requirements of a smoke-free powder, but it was still so brisant when used alone as to produce too high gas pressures and too irregular initial velocities.

London's first 'gents' public toilets were opened in Fleet Street in 1851, followed in 1852 by a 'ladies' toilet at 51 Bedford Street, Strand.

Pedial class