BLOOD, MORBID CONDITIONS OF THE. 



418 



The specific gravity of morbid serum has 

 been much oftener ascertained than that of 

 morbid blood, and it leads to more precise 

 information. The normal proportion of salts 

 does not raise the specific gravity of serum 

 above that of distilled water more than five parts 

 in 1000.* The excess beyond this increase is 

 owing to the presence of albumen. The quan- 

 tity of other animal matter is too small to be 

 worth taking into the account. Hence the spe- 

 cific gravity of serum indicates with tolerable 

 accuracy the quantity of albumen it contains. 



In some states of disease, where albumen is 

 rapidly carried out of the system, as in dis- 

 eased kidneys, in dropsies, and in profuse 

 haemorrhages, the specific gravity of serum has 

 been observed as low as l'013,f whilst in other 

 states, where water and even salts are removed, 

 as in cholera, it is found as high as 1-041 .J 



Neither the specific gravity of fibrine nor of 

 red particles has been hitherto stated by authors. 

 The former, by immersion in solution of salt, I 

 find to be 1-079 at 60 Fahrenheit. Some of 

 the latter will fall to the bottom of a solution 

 of specific gravity 1-129, and when agitated 

 with a solution of even specific gravity 1-207, 

 which is the point of saturation, will not rise 

 to the top; but the experiment is not con- 

 clusive, for the red particles certainly undergo 

 some change by the addition of salt in solution. 



The temperature of the blood is materially 

 influenced by disease. In fevers it is generally 

 though ot always above the healthy standard. 

 In the cold stage of an intermittent the tempe- 

 rature of the skin has, according to Dr. Wilson 

 Philip, been observed as low as 74 Fahren- 

 heit, while in its hot stage it has increased to 

 105. A corresponding diminution or increase 

 in the temperature of the blood in all probability 

 occurred in these cases. Haller cites authorities 

 to prove that in pleurisy and yellow fever the 

 tempeiature of the blood has been known to rise 

 to 102 and 104, in intermittent fever to 106 

 and 108, and in continued fever to 109. Mor- 

 gagni devotes several pages to the history of a 

 woman, as related in the journal of a cotempo- 

 rary, Media Via, whose blood flowed in an 

 icy cold state from the arm. The serum of 

 this blood was in small proportion and of a 

 yellow colour; the crassamentum black and 

 viscid. This person seems to have undergone 

 repeated venesection. Thackrah witnessed a 

 similar phenomenon. 



Whatever theory may be adopted respecting 

 the generation of animal heat, it is a fact which is 

 generally admitted, that it is effected through 

 the medium of the blood, that it is, catcris 

 puribus, increased in proportion to the velocity, 

 freedom, and force of the circulation, and that it 

 is mainly dependent for its development upon 

 the presence of the red particles. Wherever 

 these are deficient, either from natural disease 

 or artificial depletion, animal heat is deficient 

 likewise. Chlorotic females and those who are 

 subject to habitual losses of blood usually 



* Med.-Chir. Trans, vol. xvi. part i. p. 57. 



f Bright'g Reports, vol. i. p. 85. 



$ O'Shatighnessy's Report on Cholera, p. 29. 



suffer from coldness of the extremities. The 

 phenomenon of fainting is always accompanied 

 by diminished temperature; and whenever we 

 cut off the supply of blood from a limb, it loses 

 its natural warmth as an immediate conse- 

 quence. Plethoric subjects, on the contrary, 

 provided their circulation be unimpeded at its 

 capillary extremities, or in the process of the 

 pulmonary ventilation, are liable to preter- 

 natural heat of the surface and profuse perspi- 

 ration. As an actual diminution or increase in 

 the quantity of the red particles produces a 

 corresponding increase or diminution of animal 

 heat, notwithstanding the natural change of 

 venous to arterial blood, so likewise any cause 

 which impedes that change, although the red 

 particles be not deficient in quantity ,will produce 

 a like effect. Thus, in diseases of the heart, in 

 pulmonary obstructions, especially of a spas- 

 modic character, in the cold fit of ague, and in 

 Asiatic cholera, there is a diminution of the 

 natural warmth, although there is no reason to 

 suppose that the red particles are actually less 

 abundant than in health. 



Fibrine may undergo alterations in quality 

 during disease. In the healthy state it is com- 

 posed of definite quantities of oxygen, hydrogen, 

 azote, and carbon ; and it is quite possible that 

 some variety in the proportion of these consti- 

 tuents may give rise in disease to morbid states 

 of that principle. Huxham observes that in 

 malignant petechial fevers the crasis is so 

 broken as to deposit a sooty powder at the 

 bottom of the vessel, the upper part being either 

 a livid gore, or a dark green, and exceedingly 

 soft jelly. De Haen saw the blood in a dis- 

 solved state, and in the plague the blood is 

 said not to coagulate. 



In some persons there exists a state of con- 

 stitution, bordering no doubt upon passive hce- 

 morrhagic disease, in which the blood is ob- 

 served either to coagulate very imperfectly or 

 not at all. Alarming haemorrhages from the 

 slightest wounds are the consequence of such a 

 diathesis, and the most powerful styptics will 

 not always succeed in preventing their fatal 

 termination. Dr. Wardrop, in a small work 

 just published, has collected together several 

 interesting cases of this kind, and from some of 

 these it is demonstrated that such a condition 

 may exist in many members of the same family, 

 and even sometimes become hereditary. 



In the dead body blood is sometimes found 

 in a liquid state, resembling water, holding in 

 suspension a red, brown, or black colouring 

 matter. In this case, according to M. Andral, 

 it has been demonstrated chemically that it 

 still contains fibrine, but altered in its character, 

 so as to be no longer coagulable. This dis- 

 solved state of blood observable after death is 

 probably the same as that which exists in sea- 

 scurvy, in putrid and typhous fevers, and in 

 the latter stages of fatally terminating diseases 

 characterized by defective nervous energy. It 

 is matter of more common observation, how- 

 ever, that fibrine alters materially in its relative 

 quantity. We often find that the clot is large 

 in proportion to the serum, which may indeed 

 arise from its being loose and defective in con- 



