376 



Prof. A. Gamgee and Mr. A. Croft Hill. 



[Jan. 31, 



The latter part of the paper deals with the extension of Paschen's 

 law to spark lengths mnch shorter than those actually used in the 

 experiments, and evidence is adduced in support of the conclusion 

 that the law is applicable for discharges in a uniform field in any gas, 

 as long as the spark length is greater than the diameter of the sphere 

 of molecular action. 



" On the Optical Activity of Haemoglobin and Globin." By 

 Arthur Gamgee, M.D., F.Pi.S., Emeritus Professor of 

 Physiology in the Owens College, Victoria University, and 

 A. Croft Hill, M.A., M.B., late George Henry Lewes Student- 

 in Physiology. Eeceived January 31, — Eead February 12, 

 1903. 



Introductory Observations. 



All observations hitherto published concerning the optical activity 

 of the albuminous substances have led to the conclusion that the 

 bodies thus designated, whether derived from the vegetable or the 

 animal kingdoms, without a single exception, deviate the plane of 

 polarisation to the left, no case having hitherto been known either of 

 a dextrogyrous, a racemic, or an otherwise inactive albuminous sub- 

 stance.* 



There is one group of albuminous substances which, notwithstand- 

 ing the fact that it includes bodies of paramount physiological and 

 chemical interest, has hitherto been completely neglected, in so far as 

 the investigation of the optical activity of its members is concerned. 

 The group to which we refer is that which has been designated by 

 German writers the group of the " Proteide." This group comprises 

 those complex albuminous substances which can, with greater or less 

 ease, be split up into, or which yield as products of decomposition, 

 on the one hand, albuminous bodies, and on the other, such bodies 

 as colouring matters, or nucleins and nucleinic acids and the purin- 

 bases which result from the decomposition of the latter. The best 



# Whilst this paper was being printed, it has come to our knoAvledge that the 

 late Professor Alexander Schmidt, of Dorpat, described under the name of Cyto- 

 globin, what was certainly a mixture of impure nucleoproteids which he separated 

 from the soluble constituents of many animal cells. He definitely recognised the 

 dextrorotatory properties of this product. For information on A. Schmidt's work, 

 the reader is referred to the "Supplementary Bibliographical Note" at the end 

 of the paper by Gamgee and W. Jones " On the Nucleoproteids of the Pancreas' 

 Thymus, and Suprarenal Grland, with especial reference to their Optical Activity."" 

 Infra, p. 385.— March 5. 



