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.)

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    Any further information we receive concerning the red part of the blood is by means of magnifying glasses, which appear to give a good deal of information. They show us that the red part is composed of bodies of a globular form, swimming in the lymph and serum of the blood. This circumstance of the red part having form probably led anatomists to pay more attention to it than it deserves; as if they could thence explain any essential principle in the blood or animal economy. This knowledge is of late date; for such examinations of minute bodies could only have taken place since the invention and applica- tion of magnifying-glasses. Malpighi was probably the first who employed the microscope for this purpose ; and he, in 1608, wrote a description of the appearance of the globules in the blood-vessels of the omentum, which he mistook, however, for globules of fat. Microscopical observations were pursued with great ardour by Antonius Van Leewenhoeck, who saw the red globules, August the 15th, 1673. These early observers probably imagined more than they saw. 400 grains of colouring matter yielded on incineration five grains of ashes, which on accurate analysis were found to contain Oxide of iron 500 Subphosphate of iron 7-5 Phosphate of lime with a small quantity of magnesia . 6-0 Pure lime 20-0 Carbonic acid and loss 16*5 1000 (Med. Chir. Trans., iii. 216; Engelhart in Edin. Med. and Surg. Journ., Jan. 1827; and Rose in the Ann. de Chim. et de Phys., xxxiv. 268.) The exclusive presence of iron in this element of the blood, joined to the known tendency of the peroxide of this metal to form salts of a red colour, has generally induced chemists to suppose that the colour of the blood is due to this cause. Those who wish to consider the arguments on this subject are referred to Berze- lius (ubi ut supra) and Dr. Bostock {Physiology, i. 460). I shall here only ob- serve, 1st, that the tints produced by reagents on the blood and on the compounds of iron are wholly dissimilar; and 2dly, that the intensity of colour is too great to allow us to refer it to the minute quantity of iron present in the blood. Dr. Ure has ingeniously suggested that the colour of the blood may possibly depend on the sulphocyanate of potash, this substance having been discovered in the saliva, at the same time that it strikes with the peroxide of iron a very deep and abundant tint much Tesembling that of the blood. Dr. Williams, on the authority of Dr. Maton, mentions the case of a lady whose perspiration, when profuse, dyed the clothes on some parts of her person, particularly the wrists and neck, of a bright crimson colour, which was supposed by Dr. Prout to be caused by the sulphocyanate of iron. {Med. Gazette, xvi. 724.) But the explanation of this subject by Mr. Brande is by far the most plausible. He supposes that the tint of haematosine is owing to a peculiar colouring principle, capable, like cochineal or madder, of acting as a dye and of combining with metallic oxides. Pieces of calico impregnated with solutions of corrosive sublimate or nitrate of mercury, and afterwards immersed in an aqueous solution of haematosine, acquired a per- manent dye of a fine lake-red, unchangeable by washing; nnd solutions of oak bark gave a colour very nearly equal to that of madder and tolerably permanent The Armenian dyers have for a long while been in the habit of employing it in combination with madder, in order to insure the permanency of that colour. (Phil. Trans. 1812.)]