If solar radiation is indispensable to the decomposition of carbonic acid and the building up of the primary substances in the case of higher vegetable life, it is still possible that certain inferior organisms may do without it and nevertheless yield the most complex substances, fatty or carbo-hydrate, such as cellulose, various organic acids, and proteic matter; not, however, by borrowing their carbon from the carbonic acid which is saturated with oxygen, but from other matters still capable of acquiring oxygen, and so of yielding heat in the process, such as alcohol and acetic acid, for example, to cite merely carbon compounds most removed from organization. As these last compounds, and a host of others equally adapted to serve as the carbonaceous food of _mycoderms_ and the mucedines, may be produced synthetically by means of carbon and the vapour of water, after the methods that science owes to Berthelot, it follows that, in the case of certain inferior beings, life would be possible even if it should be that the solar light was extinguished.[161] Footnote 111: It has been remarked in practice that fermentation is facilitated by leaving the grapes on the bunches. The reason of this has not yet been discovered. Still we have no doubt that it may be attributed, principally, to the fact that the interstices between the grapes, and the spaces which the bunch leaves throughout, considerably increase the volume of air placed at the service of the germs of ferment. Footnote 112: [NaHSO_{2}, now called _Sodium hyposulphite_. See p. 355, footnote.—D.C.R.] Footnote 113: [This appears to be a misprint for 1·638 grammes = 25·3 grains.—D.C.R.] Footnote 114: [200 c.c. of liquid were used, which, as containing 5 per cent., had in solution 10 grammes of sugar.—D. C. R.] Footnote 115: [International Science Series, vol. xx., pp. 179-182. London, 1876.—D. C. R.] Footnote 116: Page 182, English edition. Footnote 117: This figure is on a scale of 300 diameters, most of the figures in this work being of 400 diameters. Footnote 118: