1 2 APPARATUS 



An aspirating bottle on a shelf elevated two feet, with rubber tubing and glass 

 tip leading to a small aquarium jar or other desk receptacle, makes a good substitute 

 for a small sink and faucet. A Hoffman screw clamp on the rubber tube controls 

 the flow of water. 



Ordinary glass salt cellars will be found very useful, where the watch-glass is 

 employed. They may also be wrapped, sterilized, and used to contain fluids for 

 inoculating, etc. 



A glass-topped fruit jar or a specimen jar containing a disinfecting solution for 

 contaminated slides, etc., should be on every working desk. A good solution is that 

 of Harrington (corrosive sublimate, 0.8; commercial HC1, 60.0 c c.; alcohol, 400.0 

 c.c.; water, to IOOG.O c.c.). 



A very simple method of making a disinfectant similar to lysol is 

 to put one part of cresol or crude carbolic acid and one part of soft soap 

 in a wide-mouthed bottle over night. The resulting compound makes 

 a perfect solution with water and a 5% solution of this will be found 

 at least equal to a 5% phenol solution. In addition to using as a 

 desk jar disinfectant it is excellent for disinfecting faeces, sputum, etc. 



For use in making loops and needles, platinum wire of 26 gauge will be found 

 most suitable. The handle made of glass rod is preferable to the metal ones. One 

 end is fused in the flame and, holding the 3- to 4-in. piece of platinum wire, with 

 forceps, in the same flame, insert the glowing metal into the molten glass. 



For making smears from faeces, sputum, and the like, wooden tooth-picks are 

 very convenient; the kind with the spatulate end is preferable. 



When gas is obtainable, the maintaining of a constant temperature for the 

 body temperature incubator (38 C.) and the paraffin oven (60 C.) is best secured 

 by the use of some of the various types of thermo-regulators. The Reichert type 

 is the one in general use, although there are many features about the Dunham and 

 Roux regulators which are advantageous. 



If the pressure of the gas-supply varies from time to time, it is essential to regu- 

 late this by the use of a gas-pressure regulator (Murrill's is a cheap and satisfactory 

 one). 



Incubators, controlled electrically, can be obtained of certain foreign makers, 

 and are quoted in catalogues of American dealers. It is probable that the Koch 

 petroleum lamp incubator is the most satisafctory one where gas is not obtainable. 

 They should be of all metal construction, and not with a wood casing, on account of 

 the danger from fire. They cost from twenty-five to fifty dollars. 



An incubator may be extemporized by putting the bulb of an incandescent 

 electric lamp in a vessel of water. The proper temperature may be obtained by 

 increasing the amount of water or by covering the opening more or less completely 

 with a towel. The test-tubes to be incubated can be put into a fruit jar or tin can, 

 which receptacle is placed in the vessel heated by the lamp. 



Emery suggests the use of a Thermos bottle as an incubator. 



The vacuum bottle should be first warmed by pouring in warm water. After- 

 ward the bottle should be three-fourths filled with water at 100 F. 



