400 ^\m\K \ Royal Society. 



of clothing, the warming of apartments, and possibly the preven- "'■ 

 tion and cure of diseases, — conducive alike to increase of comforts 

 and health. 



Tables ai'e appended, containing a series of observations extend- 

 ing through eight months, in which not only the temperature of the ' 

 body is noticed, but also the frequency of the pulse and of respira- 

 tion^ and the temperature of the air. 



*' On Ozone." By C. F. Schoenbein, Professor of Chemistry at 

 Basle, in a letter to Michael Faraday, Esq., D.C.L., F.R.S. Com- 

 municated by Michael Faraday, Esq. 



The author finds that the peculiar substance he has denominated 

 ozone, and which, reverting to the opinion he originally entertained, 

 he now believes to be a compound of oxygen and hydrogen, is ob- 

 tained readily and in great abundance by placing phosphorus in im- 

 mediate contact with water and atmospheric air at a temperature of 

 about 30° Cent., but that none is produced when water is absent. 

 Heat was found to effect the decomposition of ozone. He infers, 

 both from his own experiments and those of M. Marignac, that the 

 presence of nitrogen, instead of being essential to ihe formation of 

 ozone, as he formerly believed, does not in reality contribute in any 

 way to the production of that substance. 



" On tlie Theory of Vision," in a letter to S. Hunter Christie, Esq., 

 Sec. R.S. By William Ford Stevenson, Esq., F.R.S. 



The author adduces two experiments, of placing before the eye an 

 object, the ends of which are marked, in a vertical position, as 

 " clearly demonstrating that objects are not presented to the mind 

 as they are found upon the retina, but in the actual position in which 

 they are placed before the spectator." 



" On the Compounds of Tin and Iodine." By Thomas H. Henry, 

 Esq. Communicated by Richard Phillips, Esq., F.R.S. 



Different properties have been assigned by different authors (as 

 Sir Humphry Davy, Gay-Lussac, Boullay and Rammelsberg) to a . 

 combination of tin with iodine. With a view to explain these dis- 

 cordances, the author instituted the series of experiments detailed 

 in this paper, and which have led him to the conclusion that the 

 substance obtained by heating tin with twice its weight of iodine is 

 a mixture of two salts, differing from each other in their composition. 

 One of these is soluble in water to a slight extent without suffering 

 decomposition, while the other is immediately decomposed on coming 

 into contact with water; the former being the real proto-iodide de- 

 scribed by Boullay, and the latter being a biniodide, a salt of which 

 no particular description had hitherto been given, but which was 

 probably the compound noticed by Sir Humphry Davy as being of 

 a brilliant orange colour. The author found that this biniodide sub- 

 limes at a temperature of 356° F., while the proto-iodide, if protected 

 from the contact of air, may be heated to redness without subliming. 

 The author did not succeed in obtaining a combination of tin and 

 iodine corresponding to the sesquioxide, although Boullay supposes 

 that such was the composition of some yellow crystals which were 



