552 



Journal of Applied Microscopy. 



New Laboratory Apparatus. 



I. AN IMPROVISED HYDROGEN GENERATOR. 



Almost every laboratory makes certain modifications or adaptions of well 

 known pieces of apparatus, formulae, and methods, such changes being often 

 convenient for conditions under which they are applied. Very often these 

 changes would not be improvements under other conditions, and not uncom- 

 monly the individual who devised them regards the changes trifling in character, 

 and presumes that, of course, some one else has similarly applied the idea 

 involved, and^that it might be presumptuous on his part to publish so simple a 

 thing. The pieces of apparatus to be described, we have no doubt, have been 



Figure I. An Improvised Hydrogen Generator. 



(Drawn by P . A . Sheaff.) 



A. Container filled with sulphuric acid up to the level shown. B. Eight to sixteen-ounce bottle turned upside 



down and closed by perforated stopper shown at C. Through this perforated stopper passes the short arm of 



the conducting tube D. It will be observed that the end of the tube within the bottle B extends above 



the acid level. Just below the large drawing is an end view of the stopper showing perforations, and 



the conducting tube D passing through the stopper. The horizontal arm of the conducting tube D 



is connected with a large piece of rubber tubing, E, and the flow of gas controlled by a Mohr's 



pinch-cock, F. Any piece of apparatus may be connected to the rubber tubing at a. If the 



connecting tube D be bent in the shape of an S at the point where the letter D is showTi, 



this S may be hooked over the top of the container to hold the bottle B out of the 



fluid when not in use. 



utilized by other workers, in one form or another, but we are unfamiliar with any 

 publication which has been made on the subject. 



During the progress of some work on the bacillus of tetanus, there was con- 

 stant need of a hydrogen generator which could be thoroughly controlled, and at 

 the same time one which could be depended upon, under all conditions, to 

 afford sufficient hydrogen for any anaerobic apparatus in use. Of the many 

 forms of hydrogen generator, none seemed at the time available, and so the 

 apparatus shown in Fig. 1 was, after some experiment, devised by Dr. Coplin. 

 It can be constructed anywhere and under almost all conditions. All that is 

 needed is a bottle, preferably a salt mouth bottle of from eight to sixteen ounces 

 capacity (bottle shown at B in illustration). A stopper with perforation, or cor- 



