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EXPERIMENTAL PHARMACOLOGY 



in size) to go with the fittings. Many of these fittings (and piping) can 

 be bought in brass but at considerably higher prices. All stock "fittings 

 have right hand threads cut in them but a left hand tap can be run down 

 into these fittings (best done in a lathe) and left hand threads thus cut 

 across the right hand ones. Thus one can frame up a square with gas 

 piping using regular fittings but the left hand joints may not be suffi- 



Round Floor Flange 

 Nipple 



Pluy Faced bushing 



Bushiny 



Fig. 375. Some of the more common types of gas pi]ie fittings. Special forms can lie 

 found in catalogues of plumbeis' and gas fitter's supply houses. 



ciently tight to hold water or steam. (Bee Fig. .>75.) If one knows 

 exactly what fittings, etc., are available he can often make out an or- 

 der for exactly the pieces which he may need for an extensive piece of 

 work and purchase from a gas fitter's or plumber's supply house the 

 fittings, piping, etc., all completely threaded and ready to screw together 

 with a wrench. The author has sometimes been surprised at the cheap- 

 ness with which such equipment may be purchased. This procedure is 



