MEASURE AND APPEARANCE OF COAGULUM. 20? 



eels that contain it; both which affections, or causes of disease, are more fre- 

 quently to be moved by the manner of taking any given quantity than by the 

 actual weight, or rather the measure thereof. If the blood, for example, be 

 drawn from a small orifice, no matter how^ rightly judged the quantity mriy 

 be, however consonant to the proportions 1 have prescribed at page t)3, yet the 

 irritation of the blood-vessels, known by the rigid feel of the artery, will not be 

 reduced, nor the animal recover, " He has been bled," is thrown in the ffiie 

 of the doctor, " and is no better : we have even preserved the blood." But tne 

 thing has not been performed with requisite skill. Among other absurdities, 

 the operator will perceive the impropriety of permitting the blood to escape 

 upon the ground, and then guessing at the quantity drawn ; than which no 

 practice can be more slovenly and fallacious. 



A measure should be provided, marked with graduated circular lines, and 

 numbered from the bottom by pints each. Glass forms the neatest vessel ; 

 but pewter offers a less brittle material in horse-medicine. The blood should 

 be preserved awhile in the vessel, that the form it assumes in coagulating may 

 be noted and remarked upon; as commonly happens most indiscreetly by all 

 bystanders, whether it be caught or not ; for very few can pronounce accu- 

 rately, upon the view, the quantity of disease the blood indicates, particularly 

 when it is on the ground ; nor yet when in a vessel, unless it be caught pro- 

 perly. 



Let the vessel be ])resented so as to catch the blood fairly, and not tnckle 

 down the sides, whereby the manner of its coagulation is affected. Blood 

 that is drawn from a healthy horse, soon congeals in nearly one uniform mass, 

 about one fifth of water only remaining at the top; from the residue you may 

 wash away the red or colouring particles, and leave a pale thick coagulum or 

 lymph. In a pound of such blood will be found these proportions — viz. 8 

 ounces of thick lymph, 5 ounces of the red or colouring particles, 3 ounces 

 watery. If the operator keeps stirring the blood until it cools, the water does 

 not separate, but the whole forms one homogeneous mass. In cases of great 

 inflammation or fever, the watery proportion is much less, and the blood is 

 then consequently more viscid or thick ; which proves that this viscidity is an 

 accompanying symptom of the disorder, as maintained in various parts of this 

 volume ; but, as the fever goes on, the animal loses appetite, and he makes no 

 more new blood ; the blood then becomes thinner in consequence of the de- 

 posite of lymph made in its circulation, and the red part predominates. On 

 the contrary, in low fever and all languishing disorders of a tardy circulation, 

 in cases of cedematous tumour, the watery part is found in the greatest pro- 

 portion, and the red part is then almost extinct ; in inflammatory fever the red 

 particles predominate, the water is nearly dried up, and the lymph greatly de- 

 creases. 



Instruments. — The fleam and blood-stick have been attacked as remnants 

 of the old school, but were unjustly stigmatized as a rude metnod of obtaining 

 blood. In the hands of judicious persons, the fleam has been found equal to 

 every purpose that was required, and when used adroitly no other means of 

 blood-letting, probably, ever will supersede it. But during the rage for im- 

 provements and new inventions, that prevailed a few years since, they sought 

 to avoid a certain clumsiness of its application by introducing the lancet to 

 general use. True it is, that the awkward method of making two or three 

 aims with the stick, before striking at the fleam, occasions the horse to shy, 

 especially whilst every vessel of the head is swelhng with olood, in c. msc- 

 quence of the application of the ligature round the neck ; and equally true, 

 that careless operators frequently cut through the vein, so as to cause subse- 

 quent disorders ; though others, again, dangerously wounded the carotid arter^ 

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