386 ]\Ir Russell on the Vibration of 



by at least 6°.75 Fahr. the average temperature of the ground 

 at Paderborn, and this excess would melt a cube of ice, having a 

 side of 934 feet. This heat is irrevocably withdrawn from the 

 interior, and yet the thermal springs of Paderborn have sustain- 

 ed no diminution of heat from time immemorial.* Chemical 

 processes, which could there give rise to such inexhaustible 

 sources of heat in the youngest secondary formations, must be, 

 or have been, carried on to a great extent indeed ! 



Oji the Vibration of Suspension Bridges and other Structures ; 

 and the Means of preventing Injury from this Cause. By 

 John Scott Russell, M. A., F. H. S., and Vice-President 

 of the Society for the Encouragement of the Useful Arts 

 in Scotland, t 



Since this paper was sent to press, my attention has been 

 directed, by Lieut.-Col. Blanchard, K. H., of the Royal Engi- 

 neers, to an account of the destruction of the third arch of the 

 chain pier at Brighton, inserted in the first volume of the Pro- 

 fessional Papers of the Corps of Royal Engineers, containing 

 observations made during the storm, and sketches of the ap- 

 pearance of the bridge on the spot, by my friend Lieut.-Col. 

 Reid, who has since distinguished himself so much by his 

 researches on storms, and who has now been so deservedly ap- 

 pointed to the governorship of Bermuda. This paper gives 

 such a perfect confirmation of the views I have taken of the 

 general nature of the vibrations that destroy suspension bridges 

 and other slender structures of a similar nature, as to shew 

 that the manner in which I have predicted that chain bridges 

 are likely to be injured, is the precise way in which this suspen- 

 sion arch was actually destroyed, and that the remedy I have 

 pointed out is the only one appropriate to the evil : indeed, so 

 precisely does my view of the matter correspond to the fact, 

 that Col. Reid's sketch of the Brighton arch, when in the 



* By far the greater number of the remaining copious springs, which 

 rise on the western declivity of the Teutoburger W aid, are also thermal ones. 

 Some, for instance, in Lippspring attain a temperature of 54°. 5. 

 t Read before the Society on the 16th of Jan. 1839. 



