A treatise on the blood, inflammation, and gun-shot wounds / by John Hunter ; with notes by James F. Palmer.

  • John Hunter
Date:
1840
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the blood, inflammation, and gun-shot wounds / by John Hunter ; with notes by James F. Palmer. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

    79/618
    in animals used for food, are called white meat. In animals which have these muscles there is commonly not so much red blood as in others where these parts are more universally red; and perhaps the red part of the blood is not pushed so far in them as in those which have it in a larger proportion. There are some animals, however, which have a larger quantity of red globules in the blood, yet have some of their muscles of a lighter colour than others : even in the human subject all the muscles are not equally red ; the muscular part of the intestines, for instance, is not equal in redness to the heart, and many other muscles. To what is this owing? Does it arise from mechanical causes'? Do the vessels become sud- denly so small beyond a certain limit as not to allow the red blood to pass? or are the other parts of the blood less tenacious? Is the red part in such not allowed to go so far? or is it a separating prin- ciple in the vessels themselves? Many circumstances in life either increase the quantity of the red globules, or make them more universal in the muscles of the same animal; thus, exercise increases the quantity of the red globules and the red colour of muscles, while there is the same quantity on the whole; or perhaps we should rather rather say that indolence decreases the quantity : this is particularly remarkable in woman; and probably the whiteness of the muscles of young animals may arise from the same cause; I suspect, however, something more ; I conceive it arises from the principle of life, influenced by accidental or mechanical causes, for the muscles of young animals are increasing in colour till they arrive at the age of maturity, and not afterwards, although they continue to use exercise. Diseases lessen the quantity of the red globules, and often render their distribution unequal. From the above account we may reason, upon the whole, that the animals which are reddest, or have the greatest number of red parts, have their blood furnished with the greatest proportion of red globules.* One would naturally suppose that the red globules were of the same colour everywhere in the same animal; this last is perhaps the case; but now we find that these globules are of different hues in the different systems of vessels in the same animal. In the more perfect animals, where there are two systems of vessels carrying the blood, viz., arteries and veins, the blood is not of the same species of red in both of them in the same animal; one red is the * [This mode of reasoning is extremely questionable. It may be doubted, for example, whether any degree of exercise would ever occasion the wing muscles of certain birds to assume the dark tint which characterizes the muscles of the legs, and e converso. According to Prevost and Dumas, birds are more vascular linn maniiniferous quadrupeds, and possess a greater number of red globules; and yet there can be no doubt that the colour of their flesh is generally paler. The same observation is equally applicable to the young of all animals. Bichat has endeavoured to show that the colour of muscles depends on some foreign substance combined with their fibres; but tiiis colour is certainly not essential to their perfect structure, for the lightest-coloured muscles are often those which are most contractile. (Bichat, Anat. Gen., ii. 327.)]