404 AGRICULTURAL BACTERIOLOGY. 



but it frequently happens that there are places in the room which 

 the disinfection cannot reach, and for this purpose it is desir- 

 able to use some gaseous disinfectant which will reach every 

 part of the room. The gas most commonly used is the fumes 

 of sulphur, which may be advantageously applied as follows : 

 The room is thoroughly closed, all cracks being sealed up, 

 even to the keyholes around the doors. Then into a metal 

 vessel is placed some ordinary sulphur, 5 pounds being used 

 for every thousand feet of space to be disinfected. The vessel 

 containing the sulphur is placed in the middle of the room, 

 preferably in a tub containing an ii.ch or two of water ; a little 

 alcohol is poured over the sulphur, the sulphur ignited, and 

 the room then completely closed by shutting the door. The 

 sulphur will burn, rilling the air with sulphur fumes. The 

 room must be kept closed for 24 hours, after which it may be 

 opened to allow the fumes to disappear. Rooms disinfected 

 in this way are found in practice to be quite thoroughly disin- 

 fected, although experimental evidence indicates that sulphur 

 fumes do not perfectly destroy all pathogenic bacteria. 



The uncertainty of sulphur has led in recent years to the use 

 of formalin gas for disinfecting rooms. The method used is to 

 close the room, sealing all cracks, as in the case of sulphur dis- 

 infection, and then to conduct into the room, frequently through 

 the keyhole by means of a rubber tube, a quantity of formalin 

 gas, generated by a special apparatus devised for this purpose. 

 This apparatus is at the present time to be found frequently in 

 the hands of Health Boards, and will be used by them. No 

 private individual will be likely to have such apparatus, and 

 consequently no further directions concerning its use need here 

 be given. 



Excreta. No lesson is more useful to learn than the abso- 

 lute necessity of taking care of all excretions from men or ani- 

 mals suffering with a bacterial disease. These excretions 

 will commonly contain the specific bacteria of the disease, 



