The Microscope. 7'^ 



account of the predominance of potassa in the blood-corpuscles, 

 whilst soda predominates in the serum. We might say, then, that 

 it exists there as a potassa haemoglobinate. 



Perhaps I may digress for a few moments to refer to the 

 rapidity with which oxygen is absorbed and given up again by 

 means of this haemato-crystalline. We may refer to Pflueger's 

 highly instructive experiments with dogs. He forced these animals 

 to inhale pure nitrogen gas; for thirty seconds the highest point of 

 dyspnoea was reached. At this point some blood was abstracted 

 under great precaution, and tested for oxygen. It was found that its 

 quantity of oxygen'had been reduced to a minimum, being 1.0 to 2 

 per cent., whilst the blood abstracted from the same animal imme- 

 diately before it inhaled the nitrogen was 18.6 of oxygen. As soon 

 as these animals were permitted to inhale again pure air, the 

 dyspnoea disappeared, and they seemed as well as ever. 



In hibernating animals the quantity of haemato-crystalline 

 diminishes gradually during the winter's sleep, and is regained at the 

 return of spring. 



One of the most wonderful qualities of this substance is its 

 high atomic weight, the highest known. It is computed by I. 

 Schmidt and Hoppe-Seyler, to be 13,280. It is one of the most 

 indestructible substances known, resisting, according to Thudicum, 

 the destructive powers of decomposition and putrefaction. In most 

 solutions it retains its characteristic features, especially its optic 

 properties. I look upon this stability and indestructibility as the 

 principal factor in animal life, and any pathological condition 

 affecting their stability, or their integrity, must also affect the stability 

 of life itself. 



Modern investigations have added but additional proof to this 

 assertion. In many instances of disease, most notably in intermit- 

 tent fever, the destructive microbes select the interior and environs of 

 blood-corpuscles, and health is slow to return unless we succeed in 

 rescuing the integrity of the haemato-crystalline. 



Let me here say a few words regarding the inquiry which is so 

 often made, whether we are able to tell in a given case by the spectrum 

 test whether the blood comes from man or not. We cannot with 

 our present knowledge and means, decide the question in a direct 

 manner. The blood of all animals give the same spectral appear- 

 ances. They all have haemato-crystalline in their blood; even the lowly 

 rain-worm yields hsemato-crystalline, which proud man claims as his 

 exclusive inheritance. A. Rillet found this substance even in the 



