and funiislied Avitli ii stcMin-jfiukot (Fif?. 1 k) whicli can he. wcrked 



its hmg diameter a square shaft (h) which bears unns (.J. j.) ar- 

 rangctl at an aii<,'le so as to act as propellers, which is kept in 

 motion by reversible gearing (k). It has also a tube connected 

 with an air-pump by means of which a partial vacuum of about 



soil li.-iving been paT-tially strained as described, is admit t(Ml to tfie 



forms a char-ge : the steam-jacket is supplied with steam at a 



dr.iwu otrand passed to the boiler fires where they are consumed, 

 the ino(loi-(ms gases produced reaching the outer air by the smoke- 

 stack at a height of 70 feet above the ground. The temperature 

 of the steam" in the jacket at the pressure mentioned is about 



■<l ,in ,itt,ulimfnt to iliis apparatus — the ammimia still 

 tli.'ir ui.ul.l piul);il)ly be no need under a properly coi 



IS c<.mmoniy employed at gas-works, I need not descril: 

 Other apparatus employed are one 3o-horse-power boilc 

 retort : a lO-horse-power engine supplied from one ( 



ilers, to move the revohing shaft, the vacuum pump, an 



