398 



Dr. H. W. Pomfret. Organic Oximides : [May 4, 



In the case of a soap solution containing 3 per cent, of KN"0 3 the 

 results of the electrical and optical methods of measurement agree 

 for thicknesses greater than 450 fifi. At thicknesses between 450 and 

 200 fifn the ratio is generally above unity, being in some cases as large 

 as 128, but there is no clear indication that its value increases as the 

 film thins, and when the thickness corresponding to the black is 

 reached the ratio is again unity. 



The paper concludes with a discussion as to the cause of the in- 

 crease of electrical conductivity in thin films. The authors point out 

 that it may be attributed either to a modification of the chemical 

 constitution of the film brought about by its tenuity, or to the forma- 

 tion of a pellicle on the surface- They prove that the experimental 

 results cannot be explained by the formation of a pellicle only, but 

 that they are consistent either with the former or with a combination 

 of both causes. To discriminate between them it will be necessary 

 to carry oat observations in gases other than air, and an apparatus 

 specially designed for this purpose is being constructed. 



II. " Organic Oximides : a Research on their Pharmacology." 

 By H. W. Pomfret, M.D., F.R.C.S., late Berkeley Fellow at 

 the Owens College. Communicated by Sir Wm. Roberts, 

 F.R.S. Received March 6, 1893. 



(Abstract.) 



Organic oximides may be concisely defined as " bodies containing 

 the chemical group ZlN^'OH attached to a carbon atom." 



These bodies may be broadly divided into two classes : (a) Those 

 whose preparation involves the use of hydroxylamine ; these are 

 known as " oximes," whence the generic name " oximide" is derived. 

 (b) Those which are prepared independently of hydroxylamine. 

 These latter may be obtained by the aid of nitrous acid, and have 

 been termed " isonitroso- " bodies. This group ~N*OH must be 

 distinguished from the true " nitroso- " group — NO. The oxime 

 group is bivalent, being regarded as a compound of trivalent nitrogen 

 with the monovalent radical hydroxyl. The true nitroso-group is 

 monovalent, two " affinities " of the nitrogen being taken up by 

 oxygen. 



There is furthermore an essential structural difference between the 

 bodies forming the subject of this research and the nitrites. In the 

 nitrites the nitrogen is attached to oxygen, whereas in these 

 oximido-bodies the nitrogen of the oxime group is attached to 

 carbon, and the larger group " C~N'OH " may be considered 

 present. 



