758 



PHYSIOLOGY. 



mean arterial and a rise in the mean venous 

 pressure. In all cases of weak cardiac action, 

 or in general of bad circulation, every applica- 

 tion of condensed air is to be disapproved of. 

 These applications may be useful in order to 

 improve, after an illness, the elasticity of the 

 lungs, or to tear a slight pleuritic adhesion; 

 but to weak persons, any application of con- 

 densed air may prove a source of danger. The 

 application of rarefied air, on the other hand, 

 may be favorable to the circulation. Applica- 

 tion of rarefied air is to be recommended dur- 

 ing expiration only ; while condensed air should 

 never be applied, if at all, otherwise than dur- 

 ing inspiration. 



W. D. Halliburton has continued his obser- 

 vations on serum, and concludes from them 

 that the proteids in the blood of birds resem- 

 ble very closely those of mammals. The pro- 

 teids in the blood-serum of cold-blooded ani- 

 mals differ from those in warm-blooded ani- 

 mals in three particulars : The percentage of 

 total proteids is smaller; the serum albumen 

 is especially diminished, not only absolutely, 

 but relatively to the serum globulin present; 

 and the serum albumen seems to be a single 

 proteid in cold-blooded animals, and can not 

 be differentiated into three by fractional coagu- 

 lation, as in birds and mammals. In all the 

 vertebrates examined the temperature of coag- 

 ulation of fibrin ogen and serum globulin was 

 approximately the same. 



During the foregoing investigations Mr. Hal- 

 liburton also noticed that the blood-serum of 

 the animals was of an orange-red color. The 

 coloring-matter was carried down with the 

 proteids when they were precipitated as a heat- 

 coagulum, and extracted from the precipitate 

 as a yellowish-green substance. From the ex- 

 amination of its properties the conclusions 

 were drawn that the blood- serum of the pigeon, 

 hen, dove, and tortoise contains a yellow lipo- 

 chrome (serum lutein), which can be most 

 readily extracted from the serum by ethylic 

 alcohol ; that this is identical with the color- 

 ing-matter of the fat of the same animals ; and 

 that its presence in the muscles of the pigeon 

 and in the muscles of the lower limbs of the 

 hen is due to there being a large amount of fat 

 mixed with the muscular fibers in those situ- 

 ations. 



George T. Kemp sets forth the conclusion, 

 derived from his experiments, that in addition 

 to the red corpuscles and leucocytes the blood 

 normally contains a third histological element 

 the "plaques." These have been variously 

 considered as young red corpuscles ; as nuclei 

 floating in the blood; as being derived from 

 the red or the white corpuscles; as being 

 fibrin ; and as being globular depositions pro- 

 duced by the cooling of the blood; but the 

 author proves that, although strong resem- 

 blances exist between the plaques and other 

 histological elements of the blood, there is not 

 yet sufficient evidence to establish a genetic 

 connection. The plaques should therefore, at 



least for the present, he regarded as independ- 

 ent elements. When the blood is drawn, the 

 plaques break down almost immediately, and 

 this is not true of any other element of the 

 blood; and this breaking down of the plaques 

 seems intimately connected, in time-relations 

 at least, with the clotting of the blood. 



Dr. William Osier, of Philadelphia, who has 

 made these plaques the subject of investiga- 

 tion for several years, expresses the opinion 

 that no evidence of a histological character has 

 yet been offered which proves the disintegra- 

 tion of the white corpuscles. The subject of 

 the relation of the blood-plaques to coagula- 

 tion, he says, is a new one. Filaments of fibrin 

 can be readily seen projecting from the granule 

 masses of the htematoblasts, and Schultze and 

 Ranvier have thought that they became cen- 

 ters for coagulation. The fibrin sets or forms 

 in a thick network about the granule-masses, 

 but it is also found, independently of the 

 plaques, in the serum, resembling free crystal- 

 line 1 bodies. That the blood- plaques are cen- 

 ters for coagulation appears to be demonstrated 

 by the introduction of a small piece of thread 

 into the active circulation. After it has been 

 left there for some minutes, it is found on 

 withdrawing it that the blood-plaques have 

 collected upon it. Red and white corpuscles 

 are also found upon the thread, but the plaques 

 are much more conspicuous, and if the thread 

 is placed in a coagulable solution, after the red 

 and the white corpuscles have been washed 

 away, clotting will promptly take place, and 

 the more abundant the plaques the firmer will 

 be the clot. 



At a recent meeting of the Physiological 

 Society of Berlin, Prof. Kronecker spoke of 

 a series of precautionary measures to be ob- 

 served in cases of saving life by an infusion of 

 common salt solution. Animals, after severe 

 loss of blood, recovered in the best and most 

 rapid manner by introducing into their blood- 

 channels a like quantity of common salt solu- 

 tion. In the case of infusions of albuminous 

 solutions, of serum sanguiuis, and even of the 

 blood of another individual of the same species 

 deprived of its fibrin, there was, according to 

 direct measurements, an invariable destruction 

 of blood-corpuscles. With infusions of com- 

 mon salt solution, on the other hand, blood- 

 corpuscles were seen to increase somewhat 

 rapidly. Certain precautionary rules were to 

 be observed in applying this agency to man. 

 In the first place, the composition of the solu- 

 tion must be such as was most compatible with 

 the human organism. A solution of 0-73 per 

 cent, exercised the least irritation on the hu- 

 man body, and was therefore the most appro- 

 priate for infusions designed to save life. The 

 addition of the carbonate of an alkali, recom- 

 mended by some, had an injurious effect. Of 

 great importance were the velocity and press- 

 ure with which the infusion was injected; 

 both should correspond with the velocity and 

 pressure in the vein into which the solution 



