TRANSACTIONS OF SECTION B. 511 



MONDAY, AUGUST 19, 1878. 

 The following Papers were read : — 



1. Notes on Water from the Severn Tunnel Springs. 

 By William Lant Carpenter, B.A., B.Sc, F.C.S. 

 The plans for the construction of this tunnel had been fully described to Section G 

 at the Bristol (1875) Meeting, by its engineer, Mr. Charles Richardson. By the 

 summer of the present year, the trial heading, part of which was to form the per- 

 manent drain of the tunnel, had been driven more than half way across under the 

 Severn, which was 2\ miles wide at that point, and had successfully passed under 

 the remarkable channel of the " Shoots." In driving through the pennant rock 

 several springs had been met with, some of which had since run dry. In the 

 opinion of the engineer, no Severn water could find its way to these springs, the 

 source of which he thought were the "backs "in the pennant. The author' had 

 analysed water from four springs, and from the Severn at various states of tide, and 

 from deep land wells in the neighbourhood, the results of which led him to believe 

 that by far the greater portion of the water flowing from these springs was derived 

 from the Severn. Details of the analyses were given. 



2. On the Thetines* By E. A. Letts, Professor of Chemistry, University 



College, Bristol. 



The experiments were undertaken as a sequel to the research made by Professor 

 Crum Brown and the author on dimethyl thetine and its compounds, and with 

 a view_ to the thorough investigation of the thetines as a group — the phenomena 

 attending their formation, the action of heat and oxidizing agents on them and the 

 difference in their properties as the series is ascended. Incidentally the action of 

 bromacetic acid on certain hydrocarbon sulphides, and the action of bromaeetic and 

 iodacetic ethyl ether on sidphide of methyl were studied. 





3. On the Spectrum of Chlorochromic Acid. By G. Johnstone Stonet 

 and Professor J. Emerson Reynolds. 

 See above, p. 434. 



4. Summary of Investigations on the Pyridine Series. By Dr. W. Ramsay. 



These bases, which possess the general formula C«H a „_ 5 , are tertiary bases 

 They form an additive product with iodides of alcohol radicals, of which a good 

 example is C 5 H 5 N.CH,I, best named pyridine methyl-iodide, as it resembles a 

 salt in its constitution. They are not attacked by nitrous acid; and the cyanate 

 when heated, undergoes no molecular change, but merely splits up into the base' 

 and the usual polymer of cyanic acid, cyanuric acid. 



* For a detailed account of the.above, see ' Trans. Roy. Soc. Edin.' 1878. 



