1864.] Irtfluence of Physical and Chemical Agents upon Blood. 157 



authors were desirous of examining whether iodine would give a spectrum 

 of the first order the reverse of the absorption-spectrum at ordinary tem- 

 peratures. The vapour of iodine in an oxyhydrogen jet gave, indeed, a 

 spectrum of the first order, but it did not agree with what theory might 

 have led us to expect. 



In the electric discharge, arsenic and mercury gave only spectra of the 

 second order. The metals of the alkalies sodium, potassium, lithium, 

 thallium show, even at the lower temperature of Bunsen's lamp, spectra of 

 the second order. 



Barium, strontium, calcium in the flame of Bunsen's lamp show bands 

 like spectra of the first order, and in each case a well-defined line-like 

 spectra of the second order. On introducing chloride of barium into an 

 oxyhydrogen jet, the shading of the bands was resolved into fine dark 

 lines, proving that the band-spectrum of barium is in every respect a 

 spectrum of the first order. 



Spectra of the first order were observed in the case of only a few of the 

 heavy metals, among which may be particularly mentioned lead, which, 

 when its chloride, bromide, iodide, or oxide was introduced into an oxy- 

 hydrogen jet, gave a spectrum with bands which had a channeled appear- 

 ance in consequence of a shading by fine dark lines. 



Chloride, bromide, and iodide of copper gave in a Bunsen's lamp, or the 

 oxyhydrogen jet, spectra with bands, and besides a few bright lines. The 

 bands in the three cases were not quite the same, but differed from one 

 another by additional bands. Manganese showed a curious spectrum of 

 the first order. When an induction discharge passed between electrodes 

 of copper or of manganese, pure spectra of these metals, of the second 

 order, were obtained. 



March 10, 1864. 

 Major-General SABINE, President, in the Chair. 

 The following communication was read : — 



" On the Influence of Physical and Chemical Agents upon Blood ; 

 with special reference to the mutual action of the Blood and the 

 Respiratory Gases.^^ By George Harley, M.D., Professor of 

 Medical Jurisprudence in University College, London. Com- 

 municated by Dr. Sharpey, Sec. R.S. Received March 3, 

 1864. 



(Abstract.) 



This communication is divided into two parts. The first is devoted to 

 the investigation of the influence of certain physical agencies, viz. simple 

 diffusion, motion, and temperature, and of the conditions of time and the 

 age of the blood itself. The second part includes the consideration of 



