182 BACTERIOLOGY. 



It is claimed for this method that the degree of heat 

 necessary to break up the polymerized products formed 

 is supplied, and thus a loss of formaldehyde is pre- 

 vented. A further action of the intense heat in the 

 copper tube on the solution is to partially convert the 

 methyl-alcohol contained in commercial formalin into 

 formaldehyde gas by partial oxidation, thereby pre- 

 venting the formation of methylal and increasing the 

 amount of formaldehyde. 



The apparatus consists of a closed receiver of copper 

 holding about a gallon, a coil of copper pipe attached 

 at one end to the bottom of the receiver, and, like the 

 preceding apparatus and that made by Lentz, at the 

 other, by means of a suitable connection (rubber tube 

 with gutta-percha or metallic mouth-piece), with the 

 room or apartment to be disinfected, and a heating 

 lamp (Swedish lamp or Bunsen burner). In opera- 

 tion the desired quantity of formalin is placed in the 

 receiver and the receiver is closed. The lamp is 

 lighted and the coil brought to a red heat. The valve 

 is then opened and the solution contained in the receiver 

 is allowed to pass down and into the coil in a fine 

 stream. Upon coming in contact with the heated 

 metal the formaldehyde solution is instantly decom- 

 posed, and the liberated gas is further purified as it 

 progresses through the incandescent coil. The re- 

 sults with this apparatus have been as good as those 

 obtained by the Trillat or Lentz systems. The 

 apparatus is liable to get out of order, in that the 

 valve is apt to become clogged and so stop the flow 

 of formalin until freed by a wire supplied for the 

 purpose. 



A great improvement in this apparatus has recently 



