If the clot and serum of the chyle be exa mined separately under the microscope, they will both be found to contain the chyle granule in sufficient quantity to render them white; the chyle globule, or any blood corpuscule that the specimen may have contained, will be entangled in the clot, while the oily particles will be principally found in the serum. If the coagulation has been incomplete, or the spe cimen has been agitated, some chyle globules and blood corpuscules will of course be mixed with the serum.
The chyle has been analyzed by Reuss and Emmert, by Vauquelin, by Marcct, Prout, and 13rande, by Leuret and Lassaigne and by Tiedemann and Gmeliu, but in a science so ra pidly progressive as chemistry it is desirable to adduce the most recent information bearing on the subject. I shall therefore select the ana lysis given by Berzelius, (taken from the trans lation of his treatise on Chemistry by Me. Es linger, published at Paris in 1833,) who adopts some of the opinions of Tiedemann and Gme lin, and with whose analysis of the chyle his pretty exactly agrees.
In 100 parts of chyle, taken from the tho racic duct of a horse during the digestion of a meal of oats, he obtained, after breaking up and pressing the clot, 96.99 parts by weight of serum and 3'01 of clot : the former was re duced by desiccation to 7.39 parts and the latter to 0.78 ; consequently, after evaporation, the proportions in 100 parts stood thus— Desiccated clot 0.78 Desiccated serum 7.39 Water 91.83 100.00 -- — The dry clot softened when digested in dis tilled vinegar, but without being dissolved by it to any perceptible extent. A small quantity of a brownish-yellow oil was obtained from it by the action of boiling alcohol.
One hundred parts of the desiccated serum contained— Brown fatty matter 15.47 Yellow fatty matter 6.35 Osmazotne, lactate of soda, and chlo- 16-02 ride of sodium Extractive matter soluble in water, in soluble in alcohol, with carbonate 2'76 and a little phosphate of soda Albumen 55.25 Carbonate with traces of phosphate of lime 98.61 It has been generally stated and believed that a sufficient quantity of chyle for chemical analysis could not be obtained from the lacteals before they reached the thoracic duct, conse quently, that which has hitherto been submitted to chemical examination has been taken from the trunk of the system, where it must of ne cessity have been mixed with a greater or less quantity of lymph ; the comparison therefore between chyle and lymph has never been fairly instituted. Regretting with others the defici ency in our knowledge of the relative compo sitions of these important fluids, which, though derived from such different sources, enter in combination the already circulating blood, I performed some experiments, which need not here be described in detail, for the purpose of ascertaining the quantity of chyle that might be procured from the vasa efferentia of the mesenteric glands, and found that by a little care and contrivance as much as half an ounce of perfectly pure chyle might be procured from a horse after a full meal. I now applied to Dr. G. 0. Rees, well known to me as an able and zealous investigator of the too much neglected science of animal chemistry, and re quested him to undertake the analysis of the unmixed chyle and lymph, and to institute the desired comparison between them. Dr. Itees kindly acquiesced in my proposal, and has published the result of his inquiry in one of the late numbers of the London Medical Gazette, from which I transcribe his analysis with some of his observations, the whole of which are well worthy of perusal. The fluids in question were procured from a donkey, killed seven hours after a full meal of oats and beans.
Analysis of chyle and lymph before reaching the thoracic duct, by Dr. G. 0. Rees— Chyle. Lymph.
Water 90.237 .. 96.536 Albuminous matter 3.516 .. 1.200 Fibrinous matter 0.370 .. 0-120 Animal extractive matter so luble in water and alcohol 0.332 .. 0.240 Animal extractive matter so- .. 1.319 luble in water only 5 Fatty matter .. 3.601 .. a trace.
Alkaline chloride, I sulphate and carbo Salts. with i of ce . .
sof 0.711 .. 0.585100.000 100.00 Dr. Rees describes the albuminous matter of chyle as possessing a dead-white colour, which he attributes to the admixture of a substance of a peculiar character, and upon which he conceives it probable that the white colour of the chyle depends. Will further investigation prove this peculiar substance to be derived from the chyle granule? or is the chyle granule formed of a combination of this substance with fatty matter ? This peculiar matter, Dr. Rees states, is readily obtained by agitating chyle with nether, when the mixture speedily separates into three distinct strata, the centre stratum being the substance in question ; a similar matter, he observes, may be obtained from saliva by treating it in the same way. He found it to react as follows:— " It was insoluble in alcohol, both hot and cold—insoluble in ther—miscible with water; and soluble in liquor potass. When it had been dried on platinum foil, the addition of water made it pulpy, and it was founchrAill to be miscible with that fluid, from which, 'how ever, it separated in flakes on the addition of diacetate of lead." I have now examined each part of the lym phatic system in detail, and on reviewing it as a whole, with the mind fully emancipated from the old erroneous views in physiology, and with a full conviction of the truth of the modern discoveries with respect to imbibition, endosmosis, and exosmosis, including venous absorption, as established by Magendie, Du trochet, Segalas, Delille, and others, and ad mitted by Midler, Panizza, Fohmann, Lauth, Breschet, and all the modern investigators in this interesting and intricate field of inquiry, in which 1 regret not to be able to mention the name of one of our own countrymen since the time of Cruickshank, Hewson, and Sheldon —in bringing, I say, with our present improved state of knowledge in physics and physiology, the mind to bear upon the subject of the lym phatic. system, it appears to me that we are justified in materially modifying our opinions, both with respect to the functions exercised by this system of vessels, as well as with regard to its anatomical arrangement, which has been made to depend so much upon the precon ceived physiological notions respecting it. I venture then to suggest that we are going too far in attributing to the lymphatic (since the veins also absorb) the important and universal function of interstitial absorption of the old material, previous to the deposition of the new, in the process of growth and nutrition; that it is without sufficient proof that we admit the ulcerative process to be carried on solely through the agency of the lymphatic system, or that the removal of all morbid growths or depositions is effected by the one order of ab sorbent vessels unassisted by the other ; and indeed that there would be nothing repugnant to sound reasoning, or at variance with the pre sent improved state of our knowledge, were we to confine the functions of the lymphatic system more within the bounds ascribed to the lacteal vessels during the process of digestion, viz. to select and prepare nutritious materials for the purpose of sanguification, and to deposit them in the already circulating current.