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Meïwury is made to adhere to any motiil by putting a very little sodium with the. mercuiy- -the hundredth part by -weight is ampie. The sodium mercury may, if necessary, be ■wushed off by fresh, pure mercuiy, which continúes to adhere. A oertain way to keep ante from sugar bürrels, krd cans and preservo jars, says one who lias tried it, is to tie a striiiK wet with kerosene around the barrel, cn.ii, or jar. liepeat the wotting of the string with the kerosene oil every iew diivK. An Ëaglisb inventor proposes to pump oxhnusti d 1,-am back iuto the boiler, n place of condensing it, and experunents are now bcing condwctód with an rniriae ior tcstiug the invention. Ihc iuvfiitor contends tliat "the pressmv exerted by tta steam on one side of the piston repíesetítsj by its elástío ptfwer, the same cxpresgion of power in preesure on the othor sido, so thnt the elr.sti:1 Aiêt"ê is :ilways re;u1y to Rive litck ',}-,( exact power expended for its Cxpri ssion." .