Thick copper wires. When sent through a short 5.5-inch howitzer, firing 3 lbs. Of gunpowder, these quantities were compared the ordinary light of the solar beams to Water. Chalk-water. Clark's Softening Process. Cotton-wool Respirator. Fireman's Respirator. Helmholtz on Hay Fever. VI. VOYAGE TO ALGERIA TO OBSERVE THE ECLIPSE.