Evening Republican, Volume 21, Number 305, Rensselaer, Jasper County, 31 December 1918 — POPULAR SCIENCE [ARTICLE]

POPULAR SCIENCE

Mertrtcnlly operated, a combined brush and vacuum machine has been invented, for cleaning blackboard erasers. Tubes made of glass have been invented in Europe for handling petroleum, gasoline and some gases in place of rubber tubing. The heating value of one cord of seasoned hiekery, oak, beech, birch, hard maple, ash; elm, locust or cherry wood about equals that of one ton of coat