269 



ing, and the author describes the general appearances of the diseased 

 parts, among which ossification of the arterial trunks was prevalent. 

 He trusts that he has proved that coagulation of the blood in an 

 aneurismal sac, by the means pointed out in this paper, is not only 

 practicable, but that it may be resorted to without the production of 

 any important local or constitutional symptoms. 



Sir Everard next details the results of several experiments made 

 with a view of ascertaining the effects of various temperatures upon 

 the spontaneous coagulation of the blood. The separation of serum 

 he finds considerably impeded by a high temperature, but by a 

 heat of 120 the blood is rendered buffy; and if drawn from the arm 

 into a cup immersed in boiling water, and kept for some hours at that 

 temperature, it does not form a complete coagulum. A low tempe- 

 rature also interferes with its perfect coagulation ; for when drawn 

 into a cup immersed in ice, and left there, in twenty-four hours the 

 surface had a buffy coat, and the coagulum was extremely loose. 



It has been generally believed that the cupped appearance of blood 

 depends upon the coagulable lymph being more contractile when se- 

 parated from, than when blended with, the other parts of the blood. 

 In a patient who suffered under inflammation of the brain, and who 

 was bled in the course of thirteen days to the amount of sixty-eight 

 ounces, some of the blood, though very buffy, was not at all cupped. 

 Its appearance was very peculiar, and the coagulum was divided into 

 an upper dense portion, having the characters of coagulated albu- 

 men ; while the lower portion had a gelatinous appearance, and ex- 

 hibited the albumen in a very attenuated state, mixed with the 

 colouring matter. 



On the mathematical Theory of Suspension Bridges, with Tables for 

 facilitating their Construction. By Davies Gilbert, Esq. V.P.R.S. 

 SfC. Communicated March 9 ,1826. Read March 9, 1826. [PAiY. 

 Trans. 1826, Part III. p. 202.] 



In this paper the author states that his attention was first directed 

 to a consideration of suspension bridges, when the plan for the Menai 

 Bridge was submitted to the Commissioners of Roads and Bridges. It 

 then appeared to him that the proposed depth of curvature was in- 

 sufficient for insuring a due degree of strength ; and this opinion 

 was confirmed by some investigations, which are printed in the 

 Quarterly Journal of Science. In consequence of this, the interval 

 between the road- way and the points of support has been augmented 

 to 50 feet, and its strength now appears sufficient. 



The object of this paper is the expansion of the formulae, from 

 which the above-mentioned approximation was derived, into tables 

 adapted to general use ; and the derivation of other formulae and 

 tables for the catenary of equal strength ; a curve not merely of spe- 

 culative curiosity, but of practical use when bridges of very wide span 

 are to be constructed. The author first remarks, that as all catenaries, 



