On the origin of muscular power / by E. Frankland.

  • Frankland, Edward, 1825-1899.
Date:
1866
Catalogue details

Licence: Public Domain Mark

Credit: On the origin of muscular power / by E. Frankland. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Owing to the want of these data, the numerical results of the experiment of Fick and Wislicenus are rendered less con- clusive against the hypothesis of muscle-oxidation than they otherwise would have been; whilst similar determinations which have been made by Edward. Smith, Haughton, Playfair, and others are even liable to a total misinterpretation from the same cause. I have endeavoured to supply this want by the calorimetrical determination of the actual energy evolved by the combustion of muscle and of urea in oxygen: but, inasmuch as uric and hip- puric acids frequently appear in the urine as products of a less perfect muscle-oxidation, I have also determined the calorific value of these substances, and have added purified albumen and beef fat to the list. Creatin wrould also have been included ; but, although I was furnished with an ample supply of this substance through the kindness of Dr. Dittmar, all attempts to burn it in the calorimeter were fruitless. In numerous trials under varied conditions it always exploded violently on ignition. The determination of the actual energy developed by the com- bustion of the above-named substances is surrounded by formi- dable difficulties, which have probably prevented their previous execution. It is impossible to effect their complete combustion in oxygen gas, under conditions which permit of the accurate measurement of the heat evolved; but preliminary experiments showed that complete oxidation could be secured by deflagration with potassic chlorate; and, although this method is doubtless inferior in accuracy to the calorimetrical methods usually em- ployed, it is hoped that, with the corrections described below, the results obtained merit sufficient confidence to render them useful in subsequent discussions of this and allied subjects. The determinations were made in a calorimeter devised some years ago by Lewis Thompson, and which I have repeatedly used with satisfaction in other determinations of a like kind. This in- strument consists of a copper tube made to contain a mixture of potassic chlorate with the combustible substance, and which can be enclosed in a kind of diving-bell, also of copper, and so lowered to the bottom of a suitable vessel containing a known quantity (2 litres) of water. The experiments were conducted in the following manner:—19*5 grams* of chlorate of potash, to which about one-eighth of manganic oxide was added, were intimately mixed with a known weight (generally about 2 grams) of the substance whose thermal value was to be deter- mined ; and the mixture being then placed in the copper tube above mentioned, a small piece of cotton thread, previously * I follow the example of the Registrar-General in abbreviating the French word gramme to gram.