Physiological and pathological researches / being a reprint of the principal scientific writings of the late T. R. Lewis ... Arranged and edited by Sir William Aitken ... G. E. Dobson ... and A. E. Brown.
- Timothy Richards Lewis
- Date:
- 1888
Licence: Public Domain Mark
Credit: Physiological and pathological researches / being a reprint of the principal scientific writings of the late T. R. Lewis ... Arranged and edited by Sir William Aitken ... G. E. Dobson ... and A. E. Brown. Source: Wellcome Collection.
Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.
825/920 page 643
![teaching, the leading object which has been ordinarily kept in view in the con- struction of dietaries has been to increase the nitrogenous elements in the food proportionately, and this in a somewhat arbitrary fashion, to the amount of work exacted. 6. On the strength of this doctrine it has frequently been assumed that the working population of this country, and especially the rice-consuming portion of it, is under-fed, seeing that the amount of albuminous material which enters into their ordinary food is evidently far too small to compensate for the waste of the muscular tissue which the work they perform was supposed to entail. The great distance which a palanquin-bearer, for example, will often travel on food containing an extremely small proportion of nitrogenous material has astonished many European observers, the quantity of albuminates in his food being quite inadequate to replace the waste of muscle which, it was supposed, must have taken place in carrying himself and his burden. Every-day experience in this country, therefore, seemed to contradict the doctrine that physical labour and destruction of the nitrogenous muscular tissue should be looked upon as almost synonymous. 7. This experience is quite in accord with the teachings of the leading physiologists of the present day. In opposition to Liebig, who admitted that the heat but not the motion of the body was due to the oxidation of combustible matters, J. R. Mayer (so far back as 1845) maintained that the chemical force contained in the ingested food and in the inhaled oxygen was the source of the motion as well as of the heat. The truth of this statement has been confirmed by many observers, and during recent years Mayer's researches have been greatly extended. Conspicuous amongst these researches are the experiments which have been made on men and animals by Professors Pettenkofer and Voit, and which, amongst other things, have conclusively demonstrated that the amount of nitrogen excreted by the body during rest is so nearly the same as during exertion that the possibility of power being dependent on nitrogenous waste is, virtually, excluded. These observations, and many others of a like character,* have a very practical significance as regards the question of the most suitable dietary for a labouring population, and it would clearly be a mistake to continue formulating scales of diet based on a doctrine which is no longer tenable. 8. Indeed, the present tendency is to invert the doctrine of Liebig, and to hold that it is carbonaceous and not nitrogenous material which is chiefly consumed during mechanical action. In a recent lecture delivered before the British Association, Pro- fessor Burdon-Sanderson says:— In what may be called ' commercial physiology,' the physiology of trade puffs, one still meets with the assumption that the material basis of muscular motion is nitrogenous; but by many methods of proof it has been shown that the true Del in der Flamme des Lehens is not proteid [or albuminoid] substance but sugar or sugar-producing material.f Although, according to the most recent * A very carefully prepared account of the principal of these will be found in Chapter IX of Gamgec's PJrijdolo(/ical CJiemistry of the Animal Body.—Yol. I, 1880. t Nature, September 8th, 1881, page 440.](https://iiif.wellcomecollection.org/image/b21296996_0829.jp2/full/800%2C/0/default.jpg)
