MBTALLUB0T. 



It not incra*ed. but 'rrH^Hi If tubd ol 

 by lh preaenw of .m.ll quaatiUoi of Uiol guu 



^ from bottom totflplTtW 



otrk*J coodu <*lurl. moml Mnmo 



Tbe formation of olowholoi in tht minnfno Tho Alum u 



tha dtoortod when cold, or -Drained 

 b tJeetro-nmUre to unstrained fUel ; contact with tbe , 



I . . 



DMOHIOO 

 oold i liieraam to rtrrogth. for wbleb 



Teifnt kinds art rtt oo 



are aftrrwani 

 r otherwbe 

 ' 

 that boiler pwtM which 1 



corrode more, rapidly than tnoat WM built to 

 wkien ha** not be0n ao trrated.. Tney wor IS tt 



theoreticAllT Mfiflfant Wtr 



wbol* b wrll work- 



::-. VI - - H 

 dtooa BWt w*i tW ateait 



olphmle to tbon 

 > Milnhata *i*i 



^%i|"' Ml 



alnm. Tb brick* arv 

 The alum ft 



prwipilati.>n of th* 



