73 8 THE POPULAR SCIENCE MONTHLY. 



the same healthful condition. This one assumes a branched or tree- 

 like form, and is, if possible, more elegant and beautiful than the last. 

 Its zoothome, when fully expanded, seems to completely hide the 

 whole corallum, and nothing is visible but one mass or tree of living, 

 moving flowers. 



This polyp does not elongate itself so much as does Astrangia, and 

 its tentacles are much shorter ; and, instead of being white, it is of 

 an umber-like color, and covered all over with iridescent hues. Its 

 septa, or radiated plates of the corallum, are the same as in Astran- 

 gia. The common mass of coral is of a more solid, stone-like nature ; 

 the epitheca, or outer coral layer, which the Astrangia has not, and 

 the endotheca, or coral inside the cells, are also more compact and 

 hard. 



~+++~ 



POISONS OF THE INTELLIGENCE. CHLOEOFOKM. 1 



By CIIAELES EICHET. 



CHLOROFORM is a colorless, volatile, oily liquid ; it is denser 

 than water, and does not mix with it. It was discovered 

 by Soubeiran in 1831, 2 and Soubeiran's process for obtaining it 

 is still in use, viz., distilling alcohol with calcium hypochlorite and 

 lime. The hypnotic properties of chloroform were discovered in 1847 

 by Flourens, a few months after Jackson had recognized similar 

 properties in ether ; but the first surgeon who made use of it in an 

 operation on the human subject was Simpson, of Edinburgh, in Novem- 

 ber, 1847. Since then, the use of chloroform has become so general, 

 that nowadays no great operation in surgery is attempted without 

 employing it. We may, therefore, justly regard the discovery of 

 surgical anaesthesia as one of the greatest scientific achievements of 

 the present century, so fruitful of benefits to the human race. 



The principal effect of chloroform is the paralysis of sensibility, 

 or anaesthesia. In so far forth it acts upon the mind, for sensibility 

 is only one of the forms of mind ; but this point, which as yet is 

 rather obscure, calls for a few words of explanation. 



Two great functions devolve upon the nervous system, sensibility 

 and motion : it is through sensibility that we receive impressions 

 from without ; and it is through the excitation of the muscles, or 

 movement, that we manifest our will, or act upon external objects. 

 In the absence of both disease and poisoning, the will that is, the 



1 Translated from the Revue des Deux Mondes, by J. Fitzgerald, A. M. 



2 The first discoverer of chloroform for it was discovered independently by at least 

 three chemists was Samuel Guthrie, of Sackett's Harbor, New York. His discovery an- 

 tedates Soubeiran's several months. Liebig's discovery of chloroform was intermediate 

 between Guthrie's and Soubeiran's. Translator. 



