The Evolution of Medical Science. 145 



Fabricus showed that all valves were turned toward the 

 heart. William Harvey, at the beginning of the 17th 

 Century, opened upon himself the flood-gates of theolog- 

 ical abuse by making a remarkable discovery, while ex- 

 perimenting with these valves. He demonstrated the 

 circulation of the blood, which in those days was an exceed- 

 ingly impious suggestion, as ic showed how men and 

 animals could live without the incessant tinkering of the 

 Almighty to keep them alive. 



From this point, physiology swept grandly on, and it 

 was aided by innumerable discoveries in the new science 

 of Chemistry. The laws of digestion, respiration, secretion, 

 excretion, reproduction, nervous and muscular action, mo- 

 tions of the chjde, etc., were soon discovered. On the 

 establishment of Physiology, Pathology appeared, and the 

 anatomical lesions of disease became a special line of study. 

 Each new branch, as it came forward, reacted upon and 

 aided in the advancement of all its predecessors, as well as, 

 in time, of its successors. Inflammation, suppuration, ex- 

 travisation, new formation, mal-circulation, degeneration, 

 and kindred topics, were studied as to their causes and 

 methods of cure. This gave rise first to Histology, and 

 afterwards to Bacteriology, the last of which is at present 

 making a great deal of stir in the earth.* 



I have not stopped along the way to show how therapeu- 

 tics begat JNIateria Medica and Chemistry, nor how they 

 in turn evolved Pharmacy ; but these, and many more, con- 

 stitute branches from the developing tree. Beginning as 

 an indefinite, incoherent mass of chaotic facts and fancies, 

 slowly it has grown to its present august proportions, vuitil 

 it now appears as a definite, coherent mass of useful knowl- 

 edge, ditt'erentiated into a large number of quite distinct 

 and orderly departments of science. 



Before the advent of the last named branch, the race had 

 become conscious of the fact that, for some reason, cleanli- 

 ness was necessary to comfort, and to freedom from diseases 

 of a contagious character. The reason was quite unknown. 

 Plagues and pestilences of various kinds had shown a sort 

 of aflinity for the filthy, and while the scythe of death did 

 not cut quite a clean swathe along such a line, it succeeded 

 quite well for an approximation. Our deluded forefathers 



*Vide Cruikshank's Practical Bacteriology, Sternberg's Magnin, Belfield's 

 Jlicro-organisms, etc. 



