34 BULLETIN OF THE LABORATORIES 



are not likely to be supplied to laboratory buildings for some 

 time except as they may be required in physical laboratories for 

 study of the currents themselves. 



There seems to be an increasing demand in laboratories for 

 conveniencies and special facilities. A constantly increasing 

 proportion of the science work has to be done by laboratory 

 methods, while there is often no corresponding increase in the 

 number of instructors and assistants. It is hoped that this 

 paper may prove useful to some in devising ways of making 

 their laboratories more efficient without thereby increasing their 

 own cares and labors. 



