4 6 PLANT PHYSIOLOGY 



results; and (c) in its permission of the constant. use of quanti- 

 tative methods, which are the only prolific ones in the advanced 

 phases of any science. 



A very obvious reason for the comparatively small use of 

 normal apparatus in the past has been the small amount of it 

 that was obtainable, and this deficiency has proved a most seri- 

 ous hindrance to the progress of Plant Physiology. It is for 

 this reason, and no other, that I have undertaken in recent 

 \vurs to develop normal apparatus for the use of my own stu- 

 dents; and, in order to secure its skilled construction, and at 

 the same time to make it generally accessible to all who may 

 care for it, I have handed over its manufacture to the BAUSCH 

 and LOME Optical Company of Rochester, N. Y., in whose 

 hands the business arrangements wholly are. So far I have 

 prepared some sixteen pieces, which are described in this book, 

 and of which an illustrated catalogue may be obtained from the 

 makers, while other pieces are in advanced preparation. It is 

 my hope to develop efficient pieces for each of the principal 

 physiological processes. The construction of such apparatus 

 has also to some extent been taken up by other students, as will 

 be noted in a paragraph at the end of this chapter. 



Another obvious difficulty in the acquisition of much normal 

 apparatus is its expense. Undoubtedly it is expensive, as the 

 equipment for all good scientific education necessarily is. But 

 the expense is really less than at first sight appears. As readily 

 develops from a comparison, the cost of fully equipping a labora- 

 tory of Plant Physiology is no greater than, indeed is not so 

 great as that of equipping a good anatomical laboratory, with 

 is microscopes, microtomes, and other accessories, and, more- 

 over, everything is permanent and can be used many years. 

 Furthermore all the pieces need not be acquired at once, but 

 they can be obtained gradually, a few each year. 



Another matter of importance in connection with apparatus 

 concerns its terminology, upon which there is desirable just so 

 much uniformity and system as will contribute to economy and 

 efficiency. There already exists a certain good tendency in 



