176 Mr. J. M. Heppel on the [Jan. 27, 



Therm onietrical Observations at Rose Bridge Colliery. 



Date. 



Depth, 



in 

 yards. 



July 1854 1C1 



August IS54 188 



Mar 1S5S 550 



Julv 1858 600 



Mar IS, 18G8 630 



July 24,1868 665 



April 19, 1889 073 



November 18, 1868. 700 



Febniarv 22. lSdS... 736 



March 12, 1569 748 



April 17, 1869 762 



Mav 3. 1S69 774 



Mav 19. 1869 782 



Julv 8, 1869 801 



Julvl6,lSo9 808 



Tempera- Tempera- 



tore tore in 

 in open solid 

 pit. , strata. 



Blue shale , 



Warrant earth 



Blue shale 



Warrant earth 



" Raven " coal 73 



Linn and wool 75 



" Yard Coal" mine 76 



Strong blue metal 76 



Do. 76 



Shale 77 



Linn and wool, cr strong shale . 78 



Strong shale 80 



Blue metal * 79 



Strong blue shale 79 



Coal (Arley mine) I 79 



64-5 



66 



78 



80 



83 



85 



86 



87 



SSi 



89" 



90- 5 



91- 5 

 92 

 93 

 93| 



Remarks. 



All holes vertical in solid at bottom of p'.t drilled with water 1 yard deep, and 

 thermometer remained in hole thirty minutes and made airtight with clay. 



II. a On the Action of Rays of high Refrangibility upon Gaseou3 



Matter/' By Jonx TyxdaeC LL.D., F.R.S., Professor of 

 Natural Philosophy in the "Royal Institution. Received De- 

 cember 4, 1S69. 



This paper is an expansion of the Researches already communicated to 

 the Royal Society on the Chemical Action of Light on Gaseous Matter. 



(See Proceedings, vol. xvii. p. 92.) 



III. " On the Theory of Continuous Beams." By John Mortimer 

 HEPrEL, Mem. Inst. C.E. Communicated by Prof. W, J. 

 Macquorx Raxejxe. Received December 9, 1869. 



(Abstract.) 



The chief object of the present communication is to remedy some 

 acknowledged defects in the theory of the above-mentioned subject. 

 The priucipal steps by which it ha3 reached its present state of develop- 

 ment are also noticed, and may be briedv recapitulated as follows : — 



In 1825 M. Navier investigated the conditions of a straight continuous 

 beam resting on any number of supports. His method, though perfectly 

 correct for the assumed conditions (which embraced most cases occurring 



