742 



THE POPULAR SCIENCE MONTHLY 



CORRESPONDENCE. 



THE NATURE AND CAUSE OF FERMEN- 

 TATION AND PUTREFACTION. 

 To the Editor of the Popular Science Monthly. 



I HAVE read with no ordinary interest 

 the lecture by Prof. Tyndall, published 

 in your issue of December, upon the sub- 

 ject of " Fermentation and its Bearings 

 upon the Phenomena of Disease;" and I 

 desire, with your permission, to submit 

 some points suggested to my mind upon 

 which, according to my own conception, 

 there remains some doubt, and which I 

 should like to see explained. It is not my 

 intention to dwell upon the general subject 

 of the nature and causes of fermentation, 

 but merely to touch upon it, confining my- 

 self rather to the question of the causes of 

 putrefaction. 



In fermentation and the production of 

 alcohol, the presence of bacteria seems to 

 be constant. Prof. Tyndall holds that the 

 changes resulting in the formation of beer 

 and the production of alcohol are due to 

 the action of these microscopic germs, 

 which, seizing upon the grain, or fruit, 

 elaborate the spirit. Now, it does not seem 

 to me perfectly clear that the changes 

 which take place in the fruit may not be 

 purely chemical, and that a portion of the 

 component elements of the fruit, not requi- 

 site to form the chemical combination of 

 alcohol, becomes a suitable soil in which 

 the air-germs can take root and grow. It 

 is a question of cause and effect. 



Again, a certain amount of moisture is 

 necessary to the production of mould. It 

 may be asked : Is it quite certain that the 

 moisture is not the agent of a chemical de- 

 composition, and that the growth of mould 

 is due to the deposit of seed in soil fur- 

 nished by this decomposition ? May it not 

 be that a dry and cold atmosphere pre- 

 vents or retards chemical decomposition in 

 devitalized organic matter, while heat and 

 moisture cause or facilitate it ? Why 

 should we disregard the chemical forces in 

 the decomposition of organic matter de- 

 prived of vitality ? Or, does Prof. Tyndall 

 wish us to regard all organic matter as 

 possessed of vitality until it is decomposed ? 

 Indeed, he says : " Cherries, apples, peaches, 

 etc., are composed of cells, each of which 

 is a living unit ; " and " the living cells of 

 fruit can absorb oxygen and breathe out 

 carbonic acid, exactly like the living cells 

 of the leaven of beer." We know that the 

 seed of fruit possesses vitality; but is it 

 proof of vitality in the cells, that certain 



changes take place between the constitu- 

 ents of the cells and the external air, and 

 that other changes take place when the 

 fruit is excluded from the air ? Granting 

 it is, then shall we say that all vegetable 

 products, although long since uprooted but 

 undecomposed, are possessed of life ? Are 

 the cells which compose the well-worn oak- 

 beams of the few remaining wooden walls 

 of Old England still endowed with vitality, 

 and constantly engaged in a struggle for 

 life with the low forms of animated Na- 

 ture ? Then, if this be conceded, might 

 we not assume that fructification of germs 

 is likewise essential to the decomposition 

 of minerals ? If the decay of an old boot 

 is dependent upon the growth of mould, 

 may we not suppose that the rusting of an 

 old axe is due to similar influences ; and that 

 the erosion of rock, which in time forms 

 abundant soil for vegetation, is the work of 

 microscopic germs, although commonly sup- 

 posed to be due to physical forces ? 



Prof. Tyndall says that " some of the 

 numberless air-germs produce acidity, some 

 putrefaction." But when acidity takes place 

 rapidly, as in a frozen apple just thawed, 

 and with an unbroken skin, are we still to 

 regard it as the result of bacteria ? With 

 regard to putrefaction, Prof. Tyndall cites 

 a number of experiments with beef-tea. 

 Now, to make these perfectly satisfactory, it 

 seems to me that the fluid ought to be ex- 

 posed to not a limited quantity of pure air, 

 but a free change of air from which all 

 motes had been removed. 



I now come to the subject of putrefac- 

 tion in connection with the living body, and 

 the antiseptic treatment of wounds as 

 taught by Prof. Lister, of Edinburgh. 

 Prof. Tyndall says that he has obtained "a 

 specific against putrefaction and all its 

 deadly consequences." This statement 

 might lead the public to believe that the 

 teachings of Prof. Lister were generally 

 accepted by the medical profession. Such, 

 however, is by no means the case, notwith- 

 standing his practice has been thoroughly 

 tried in most if not all the principal hos- 

 pitals of Europe and America. While a 

 certain number have adopted his method, 

 the majority have rejected it, with the con- 

 viction that other treatment less trouble- 

 some is quite as, if not more, successful. 

 That Prof. Lister's theories and practice are 

 not believed in by the representative sur- 

 geons of the United States, was clearly de. 

 monstrated at the late International Medical 

 Congress, at Philadelphia. Prof. Lister was 



