1.—PHYSIOLOGY. 135 
again, we may see it as a steady progress towards synthesis, towards 
the unification of all the contributory functions of the parts into a 
‘single functional organism. 
The analysis of the separate functions of each part of the body was 
an inevitable mental process as the anatomist revealed more and more 
accurately the visible machinery of the body. Bichat at the beginning 
‘of the nineteenth century had taught that the activities of the body 
‘must be the sum of the activities of the organs. The announcement 
of the universal cellular structure of the organs made by Schwann 
‘seemed but to carry this analysis one step further, and to show that 
in the sum of the activities of the constituent cells could be found 
the adequate expression of the functions of the whole body. The rapid 
‘improvement of the microscope in the latter half of last century, 
‘combined with the new resources of the aniline dyes by which trans- 
‘parent structures could be differentiated and made visible, greatly 
stimulated the analytic study of the body. As the various glandular 
structures were made visible and even, as it almost seemed, the inner 
life of the gland cell was revealed, as muscle fibres in their different 
kinds were made plain and the harder elements of the body resolved 
into the architectures due to different kinds of constructive cell, so it 
seemed to many that in a little time we should have the quest resolved 
‘In an appeal to a congeries of physico-chemical events within the 
‘individual cells. Even the mysteries of the central nervous system 
‘seemed to be dissolving as the new powers of histology, coupled with 
‘refined methods of experiment, showed the intricate pattern of com- 
‘municating fibre and cell and gave provisional descriptive explanations 
of many isolated nervous phenomena. Meanwhile, the chemical 
structure, no less than the material form, of the body was being explored, 
and here, too, progress followed the path of analysis, ever more refined 
and complete. Just as old notions of ‘ humours’ of the body had been 
resolved into varieties of cell activity, so the vague chemical ideas 
‘conveyed in the words ‘ protoplasm ’ or ‘ metabolism ’ received precision 
by expression in terms of colloidal systems or of associated enzymes 
or catalysts in appropriate positions, effecting chemical changes of 
recognisable type among substances of relative simplicity. 
_ Along these lines of analysis rapid progress has been made, but 
it is to be observed that it has been in great part along diverging lines. 
‘The tendency has been centrifugal, or, to use a biological simile, the 
owth of physiology has led to a fissiparous habit. Pursuit of know- 
ledge by particular technical methods has led to specialism; men have 
reached points far distant along branches of inquiry that at first grew 
together from the stem. The very development of new technical 
‘methods may by itself lead unavoidably to separatism, for the micro- 
scope and test-tube may best be used in rooms widely different in 
equipment and often far separated in space. So have grown up new- 
named sciences within a science, and the histologist or cytologist, the 
neurologist, the pharmacologist, the biochemist—each carrying off, so 
to speak, his part of the subject—may be found to be incurring the 
dangers or even paying the penalties of schism. 
Step by step, however, with this progress in analysis. a continual 
