Show economy in smoke prevention after remarking that there can be no hope of the general adoption of means to prevent the fouling of the air ot of great cities with factory smoke unless it can be demonstrated that the adoption ot of such means will result in the saving of money to the makers of the smoke prof J A switzer of the university of of tennessee records the result ot of experiments which ho he has made with smoke consumers based on tho the principle of injecting with steam jets fresh air into the furnaces whenever fresh fuel la Is put upon the fires ile he finds that the claim that such apparatus appa ra increases tile the efficiency effle tency of tho the boilers by increasing the evaporation 81 ot the he water la Is well founded and azid that there Is a real econos economy ny tn in their usei use youths companion |