160 Prof. Tyndall — Contributions to Molecular Physics. [Mar. 17, 



The action of sulphuric ether upon blood differs in many respects from 

 that of chloroform. In the first place, ether has a powerful eifect in de- 

 stroying the blood-corpuscles, dissolving the cell-walls' and setting the 

 contents free. In the second place, ether prevents the blood from assum- 

 ing an arterial tint when agitated with air. The higher the percentage of 

 the agent, the more marked the eifect. In the third place, ether neither 

 diminishes the absorption of oxygen nor the exhalation of carbonic acid by 

 blood ; and lastly, it has a much more powerful effect in causing the con- 

 stituents of the blood to crystallize. For example, if an equal part of ether 

 be added to the blood of a dog poisoned by the inhalation of chloroform, 

 as the ether evaporates groups of large needle-shaped crystals are formed. 

 Under the microscope the crystals are found to be of a red colour and 

 prismatic shape. 



Alcohol acts upon blood somewhat like chloroform ; it arrests the che- 

 mical changes, but in a less marked degree. 



Amylene was found to act like ether upon blood, in so far as it did not 

 diminish the absorption of oxygen or retard the elimination of carbonic 

 acid. It differed, however, from ether in not destroying the blood-cor- 

 puscles. 



In the last place, the action of mineral substances is stated, viz. : — 



1. Corrosive sublimate was found to increase the chemical changes 

 which develope carbonic acid, and to have scarcely any effect on those de- 

 pending upon oxidation ; its influence, if any, is rather to diminish them 

 than otherwise. 



2. Arsenic seems to retard both the oxidation of the constituents of the 

 blood and the exhalation of carbonic acid. 



3. Tartrate of antimony increases the exhalation of carbonic acid gas, 

 while it at the same time diminishes the absorption of oxygen. 



4. Sulphate of zinc and sulphate of copper both act like tartrate of 

 antimony, but not nearly so powerfully. 



Lastly, phosphoric acid was found to have the effect of increasing the 

 chemical transformations and decompositions upon which the exhalation 

 of carbonic acid depends. 



March 17, 1864. 

 Major-General SABINE, President, in the Chair. 

 The following communications were read :— 

 I. " Researches on Radiant Heat. — Fifth Memoir. Contributions to 

 Molecular Physics.^^ By J. Tyndall, F.R.S., &c. Received 

 March 17, 1864. 



(Abstract.) 



Considered broadly, two substances, or two forms of substance, occupy 

 universe — the ordinary and tangible matter of that universe, and the 



