THE BLOOD. 37 



It may be proper to observe here, that in the hearts of animals 

 which had died without any inflammation, I have found the 

 blood entirely coagulated long before this time. And that 

 from opening them at different times, I have seen it coagulate 

 in their hearts after death, in the same gradual manner that it 

 does in their veins, when its motion is stopped by ligatures ; as 

 related in page 22. 



In the next place, that the blood is really attenuated (see Notes 

 xxi, xxui, and xxix) in inflammatory disorders, where the whitish 

 crust or size appears, is probable from the following circumstances : 

 1st. It even seems thinner to the eye. 2d. The red particles or 

 globules subside sooner in such blood than in that of an animal in 

 health. This seems proved by observing that in the above- 

 mentioned experiments, where the blood was at rest in the 

 veins, it was not covered with a crust, except in one or two in- 

 stances, though in all those cases it remained longer fluid than 

 the blood commonly does in a basin, after bleeding, where the 

 crust appears. And again, the blood in the heart of an animal 

 that dies aviolent death, is not generally covered with a white crust, 

 notwithstanding it is so late in being congealed (see Note xin). 

 These circumstances show, that something more than merely a 

 lessened disposition tocoagulate is necessary for the fonningof the 

 crust or size. 3d. The globules more readily subside in inflamma- 

 tory cases, from the surface of the whole mass of blood, than they 

 will afterwards do from the surface of a mixture with the serum 

 alone, of which the following experiments are a proof. But, before 

 I relate them, let me observe, that they were made with a view 

 to discover whether the inflammatory crust could be owing to 

 any other cause than to the attenuation of the coagulable lymph, 

 and to its disposition to coagulation being lessened : and as the 

 same appearance might be suspected to arise from an increased 

 specific gravity in the red particles, or from the serum alone 

 being attenuated, I endeavoured to decide the question in the 

 following manner : 



EXPERIMENT XVII. 



Into a phial, marked A, I put an ounce of the serum of the 

 blood of a person whose crassamentum had an inflammatory 

 crust. 



Into another, marked B, I poured an ounce of the serum of 

 a person whose blood had no crust ; then to each of these, I 



