6 14 Readings in European History Quite as astonishing is the discovery that within the root knobs of peas and beans live bacteria which, by split- ting up mineral salts containing nitrogen and by absorbing nitrogen from the air, give it over to the plant, so that it is enabled to grow luxuriantly, whereas without their presence the tiller of the soil might fertilize the ground in vain. It is quite possible that not alone peas and beans but all grasses and plants and trees depend upon the presence of such germs for their very existence, which in turn supply man and animals with their means of existence. Hence we see that these nitrifying bacteria, as they are called, if swept out of existence, would be the cause of cessation of all life upon the globe.
The astonishing effects of scientific discovery in pro- moting the highly practical art of surgery are well de- scribed by Dr. Keen in the following passage. 501. Modern Great theologians, such as a Calvin or a Jonathan Edwards, surgery. were they recalled to life, could discourse as learnedly as Dr.W. W. ever °f predestination and free will ; great forensic orators, Keen.) such as a Burke or a Webster, could convince us by the same arguments and arouse us by the same invectives that made our fathers willing captives to their silver tongues. But to-day, so rapid has been our surgical progress that a Velpeau, a Sir William Ferguson, or a Pancoast, all of whom have died within the last thirty years, could not teach modern surgical principles nor perform a modern surgical operation. Even our everyday surgical vocabulary — staphy- lococcus, streptococcus, infection, immunity, antisepsis and asepsis, toxin and antitoxin — would be unintelligible jar- gon to him; and our modern operations on the brain, the chest, the abdomen, and the pelvis would make him wonder whether we had all lost our senses, until, seeing the almost uniform and almost painless recoveries, he would thank God for the magnificent progress of the last half century, which had vouchsafed such magical — nay, almost divine — power to the modern surgeon.
