154 



KNOWLEDGE. 



[July 2, 1900. 



Arawaks. Tiie Indians of East Brazil and Ceuti-al South 

 America form a third section ; among whom the Tupi- 

 Guarani linguistic stock, whose language forms the lingua 

 franca of the eastern side of the continent, is the most im- 

 portant. To this stock belongs the tribe from Pai-a, of 

 which representatives are shown in Figs. 2 and 3. Lastly, 

 we have the Fampean and Fucginn section. Of the 

 mainland tribes of this section the more notable arc the 

 Tehuelchcs, or Patagonians, who inhabit the country 

 lying between the Rio Negro and the Magellan Strait, 

 and are the tallest of the American aborigines, although 

 somewhat exaggerated notions have been entertained 

 in regard to their height. As to the Fuegians, who are 

 restricted to the southern and western coasts of the 

 bleak island from which they take their name, space 

 only permits of the statement that they are, on the 

 whole, the most degraded and the most wretched of all 

 the American Indians. 



SOME EARLY THEORIES ON 

 FERMENTATION.-I. 



By W. St.\nley Smith, ph.d. 



In the year of grace, 1636, Thomas Hobbes, th3 famous 

 author of " Leviathan,'' wrote a letter from Paris to 

 the Duke of Newcastle. There are some sentiments in 

 this letter so expressive of the attitudes adopted by the 

 leading natural philosophers of each age, that we may 

 well use them as a prelude to our short survey of the 

 theories that have successively surrounded the fer- 

 m.entation of sugars and other materials. " In thingcs, ' 

 says Hobbes, " that are not demonstrable, of which kind 

 is the greatest part of naturall philosophy, as depend- 

 inge upon the motion of bodies so subtile as they are 

 invisible, such as are ayre and spirits, the most that 

 can be atteyued unto is to have such opinions as no cer- 

 tayne experience can confute, and from which can be 

 deduced, by lawfull argumentation, no absurdity." It 

 has been said that the essence of our modern su- 

 periority to the earlier jihilosopher consists in our 

 jiaving accumulated more facts, but a moment's 

 thought will teach us, if, indeed, the lives and works 

 of men like Huxley and Pas(.eur do not teach us, that 

 our greatest strength lies not so much in mere know- 

 ledge of facts, but rather in the acquisition of rightful 

 methods of research, and the clearing of pathways that 

 lead to Nature's most umbrageous nooks and crannies. 



Records of fermented juices, both of cereals and 

 fruits, extend as far as historical research can pene- 

 trate. Every mention of the results of fermentative 

 changes preceding the era of Christendom is distin- 

 guished by the fact that supernatural powers are 

 credited with the functions we now attribute to living 

 realities of daily life, so that Osiris and Bacchus are 

 held responsible for the early wine and beer, and we 

 may deem their adorers justified in their worship, for 

 lliey had " no certayne experience " to refute the 

 notions they held as to these deities and their 

 functions. The first name of any note is that of the 

 famous naturalist, Pliny, in whose observation of the 

 presence of an acid in the fermentation of bread we 

 discern the primitive glimmerings of investigation in 

 these dark regions; and he possesses a further interest 

 for us, in;ismuch as Pliny was probably one of the first 

 martyrs in the cause of knowledge. He died, at the 

 age of fifty-six, whilst attempting to Jiscend Vesuvius 

 during tlu' historic eruption which laid Pompeii and 

 Hcrculaneum in dust and ashes. Plutarch, who wa.s 



born in the year 48, in his works pi-esents us with 

 many curious and trite observations on the learning 

 and customs of those times, and we mention, as es- 

 pecially interesting to our subject, his remarks on the 

 benefit of warmth, and retaiding influence of cold, on 

 the progress of fermentation. 



It is to Djafer al Geber that we owe the discovery 

 of the art of distillation, besides which he appears to 

 have been the first alchemist to perform the ojJcrations 

 of filtering, evaporating, crystallising, and dissolving 

 metals in acids. Geber describes his processes in the 

 mystic phraseology of those times, and does not fail to 

 mention the " elevation of dry substances by fire, " now 

 known as the act of sublimation. Rhazes, a Baghdad 

 physician, who flourished between the years 860 — 940, 

 was the first to give accurate directions for the pro- 

 duction of aqua vitse by distillation, and means by 

 which a still more concentrated .spirit may be obtained 

 therefrom — namely, by another distillation over quick- 

 lime. 



The words fermentatio and digestio appear to have 

 been used by the early alchemists to indicate the saino 

 process, namely, a frothing or evolution of gas accom- 

 panying a chemical reaction. The substance or reagent 

 causing this evolution of "spirit" was designated the 

 ferment, whilst under putrefactio we are to recognise 

 the gradual decomposition of inorganic substances. It 

 slvpuld be remembered that the various products due 

 to vital activity were, until as late as 1828, considered 

 outside the pale of experimental science. In that year 

 Wohler synthesised ui'ea, and thus broke down the 

 barrier that had resisted the attacks of many ages. 

 The hazy ideas anent the differences between what we 

 now, for the sake of convenience, call organic and in- 

 organic chemistry, are well illustrated in writings and 

 sayings attributed to the leading thinkers of the dark 

 ages. Basilus Valentinus. lu writing the results of his 

 exjaeriments on fermentation, declares that alcohol is 

 always originally present in the fluid, from which it is 

 subsequently obtained, but that it is only by a process of 

 })uritication, or as we should now say, fermentation, that 

 the alcohol is freed from other substances, and is thus 

 able to exhibit its characteristic properties. He com- 

 pared the process to combustion, and plainly tells us his 

 researches were directed towards the discovery of an 

 universal ferment, in fact the lapis philosophorum of 

 which so much was expected. 



Libavius, a dim and obscure individual, looms forth 

 from the year 1580, or thereabouts, with an idea which 

 one, Stalil, evidently pondered deeply over. He re- 

 marks that somehow or other the substance undergoing 

 fermentation must have an affinity with the cause of 

 its decomposition, or as this cause was named, the fer- 

 ment. Libavius possessed none of the data accumu- 

 lated by modern science, anent enzymes and zynies, but 

 can we not here discern the germ of one of the latest 

 theories of fermentation, that proclaimed by Emil 

 Fischer of Berlin, and known to science as the Schloss 

 und Schlussel (Lock and Key) theory ? 



Turning now to the pages of Hoefer, Lavoisier, or 

 Kopj), we find an account of a great man. Van Hel- 

 mont, who, born at Brussels in 1577, followed the vo- 

 cation of journeyman physician, and beguiled his leisure 

 hours with much experiment and writing. The know- 

 ledge possessed by Van Helmout of various gases was 

 probably far in advance of that held by his contem- 

 poraries, but, like the earlier alchemists, he was but a 

 poor master of descriptive art. However, it is to him 

 we owe the word " gas," borrowed or derived from the 



