RECENT PHYSIOLOGY. 8i 



EECENT PHYSIOLOGY. 



By Professor G. N. STEWART. 



EVERY year a mass of original work in physiology, covering from 

 ten to fil'teen thousand pages, for the most part of formidable size 

 and closeness of print, is collected in the various special journals of the 

 science, or mingled with kindred, though miscellaneous, dust in the 

 transactions of learned societies, or decently buried at the public 

 expense in government bulletins and official reports. Those four hun- 

 dred square yards of printed matter embrace, on the average, more 

 than five hundred papers in German, English, French and Italian, 

 without reckoning stray messages in less familiar tongues, such as 

 Russian, Polish, Dutch, Spanish, the Scandinavian languages, the dog 

 Latin of graduation theses, and even, it may be Japanese, Arabic and 

 modern Greek. The great majority of these communications either con- 

 tain new facts or are directed, often with notable acuteness, to the 

 unfolding of new relations between facts previously established. It is 

 obvious that no survey of recent physiology which is possible within 

 the space at our disposal could pretend to exhaust the contents of its 

 crowded archives even for a single year. I shall try rather to trace 

 the main tendencies, while incidentally mentioning some of the out- 

 standing achievements of recent physiological discussion and research, 

 than to enter in any detail into the results of particular investigations. 

 Foremost among these tendencies is the study of the structure and 

 functions, and especially the chemical and physico-chemical relations 

 of the individual cell, in which, as has been well said by Bunge, in 

 his brilliant Lectures on Physiological Chemistry, lies ever the riddle 

 of life. While the mode of action of the complex physiological mech- 

 anisms, built up by the grouping and chaining together of cells of the 

 same or of different kinds, deserves and has attracted the most assid- 

 uous attention, it has become more and more apparent that, as we push 

 our enquiries back, we are ahvays, sooner or later, arrested at the 

 boundary of the cell. We attempt, for example, to explain the mech- 

 anism by which the circulation of the blood is maintained and regu- 

 lated, and up to a certain point we succeed tolerably well. We recog- 

 nize as the central factor the rhythmically contracting heart which 

 forces the blood through the branching arteries into the netted laby- 

 rinth of the capillaries, whence it is again conveyed to the heart by the 

 veins, and thus completes its destined round. We know that the rate 

 and force of the heart-beat and the caliber of the blood vessels are con- 

 trolled by efferent nerves carrying impulses down to them from centers 

 situated in the medulla oblongata, the portion of the central nervous 



VOL. LIX.— 6 



