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HA RD WICKE'S S CIENCE- G OSS IP. 



wasp's nest, both larvae and winged warriors, were 

 eaten with impunity, the duck's active tongue being 

 evidently proof against their stings. I have little 

 doubt that the venom of the ants is the formic acid 

 they secrete. This punishment of the duck indicates 

 plainly enough the use of this secretion. But for it 

 a creature otherwise so helpless and wingless would 

 be exterminated. Earwigs are similarly rejected, as 

 though they also emitted a similar acrid secretion. 

 Perhaps some of the readers of Science-Gossip 

 who have caged specimens of insectivorous birds 

 will be able to tell us whether ants and earwigs 

 are able to defend themselves in like manner against 

 these. I ask this question, having a vague impres- 

 sion that some such birds are occasionally fed 

 on ants or their larvae. The question of course 

 applies to the complete animal, not to the larvre 

 of the ants ; these helpless babies being so carefully, 

 bravely, and skilfully protected by their parents and 

 soldiers. 



On August 31st, Chevreul entered his hundredth 

 year. Chevreul has been a brain-worker all his life- 

 time, and a hard worker, was assistant to the 

 celebrated Vauquelin at seventeen, and published his 

 first original paper at twenty, and more than a score 

 of others during the next six years. It is said that he 

 never drank a glass of wine in his life — a wondrous 

 eccentricity in a Frenchman — and that he never wears 

 a hat indoors or out of doors for protection's sake, 

 only under conventional compulsion. A recent por- 

 trait displays a very abundant, supply of natural 

 head-covering, just thinning somewhat at the top, 

 but spreading out exuberantly on each side. 



He is still a worker ; only a year or two ago, he 

 startled his brother academicians by coolly remarking 

 in the course of some supplementary observations on 

 a communication he had just read, "Moreover, 

 gentlemen, the observation is not a new one to me. 

 I had the honour to mention it here, at the meeting 

 of the Academy of Sciences, on the 10th of May, 

 1812." 



Talking of the mild winter of 1883, he remarked 

 that the severest winter he ever experienced was 

 that of 1793- Two years ago I purchased a copy of 

 his book on " Animal Fats," commenced in 1813, and 

 published in 1823, and read it with much interest 

 and instruction. All that we know on this subject, 

 and its very extensive applications in the art of soap- 

 making, candle-making, lubricants, &c, even of 

 "bosch" (artificial butter), is based on this treatise. 

 I must not be tempted to enumerate his work, a 

 mere list of subjects would carry me far beyond 

 reasonable limits ; and there is the less need of this 

 as I hope, twelve months hence, to record his com- 

 pletion of a century of admirable life, when popular 

 biographical sketches will probably rain upon all 

 readers. France may well be proud of such a citizen. 



As all my readers know, the question of whether 

 we should use "whole meal" or ordinary flour has 



of late been very warmly discussed. The whole meal 

 advocacy is based upon chemical analyses, which 

 prove that the envelope of the grain which is cast 

 out from ordinary flour is very rich in nutritious 

 material. This evidence, however, is insufficient 

 alone. We require to know not only what this 

 portion contains, but how much of it is obtainable as 

 nutriment. The mechanical structure of the bran is 

 not promising as regards digestibility, and further 

 investigation appears to confirm the inference its 

 structure suggests. 



A paper on the subject by A. Girard was published, 

 a few months since, in the current series of the 

 " Annales de Chimie et Physique," page 289, con- 

 taining the results of careful researches on the 

 subject. The author tells us that the envelope of 

 the grain constitutes 14*36 per cent, of the whole, 

 and that it is rich in nitrogenous substances (iS* 75 

 per cent.), but they are incapable of assimilation by 

 human digestive organs, the envelope of the grain 

 passing through the body in a practically unaltered 

 condition. He asserts that the brown colour of 

 whole-meal bread is not merely due to that of the 

 bran contained in it, but chiefly to the action of 

 ccrealin (a ferment discovered in the envelope of 

 wheat by Meges Mouries), which diminishes the 

 plasticity of the gluten of the flour and gives it a 

 brown colour. 



A careful.examination of brown bread will, I think, 

 lead the reader to agree with me in accepting this 

 explanation, as an ordinary brown loaf composed of 

 a mixture of white flour and light buff-coloured bran, 

 is darker [than the bran itself, and is evidently 

 stained throughout, not merely mottled by the bran 

 particles. By comparing the colour of the baked 

 loaf with the dough before baking, this difference 

 is very obvious, and it confirms the statement of 

 M. Girard, that the change of colour occurs during 

 the baking. 



When, however, he accuses the cerealin of doing 

 mischief because it acts on starch in a manner similar 

 to the action of diastase, and diminishes the plasticity 

 of the gluten, I cannot agree with him, nor with his 

 condemnation of the embryo or germ of the grain 

 because it contains not only cerealin, but a highly 

 oxidisable oil, which he says imparts the odour of 

 rancid grease to the bread. My ground of difference 

 here is: 1st. I cannot smell this rancidity. 2nd. If I 

 could, it would prove the existence of something 

 equivalent to butter ; and bread and butter approaches 

 nearer to a complete food than bread alone. 3rd. 

 The conversion of starch into dextrine by diastase 

 is especially desirable. It must be done before 

 the starch can be digested, is done by the saliva, 

 the pancreatic juice and the intestinal juice, but is 

 better done with the assistance of vegetable diastase, 

 such as is contained in the germ of the grain (see 

 " Chemistry of Cookery," Chapters XII. and XVIIL, 

 where I have more fully discussed these subjects). 



