238 



for the advancement of which our Society was established, and which 

 tend at the same time to the glory of the nation that protects them, 

 and to the happiness of the whole civilized world." 



These Addresses were unanimously adopted by the Society. 



The following letter was read from G. G. Anson, Esq., addressed 

 to the President, enclosing a specimen of a deposit with which nine 

 acres of land near Exeter, belonging to Lord Radnor, had been 

 covered after the subsidence of a flood, and which was sent by 

 H.R.H. Prince Albert, F.R.S. :— 



"Buckingham Palace, June 8, 1840. 



My dear Lord, 



" His Royal Highness Prince Albert has commanded me to for- 

 ward to you the enclosed specimen, which has been sent up to His 

 Royal Highness from Lord Radnor's place near Exeter, where nine 

 acres of land were covered with this curious substance after a flood 

 had subsided. His Royal Highness thinks it very probable that the 

 subject may already have been brought before the Royal Society, but 

 in case it should not have been, he sends the accompanying packet. 

 It is said that a good deal of it has been applied to the purpose of 

 making waistcoats for poor people. 



" Believe me, 



" My dear Lord, 



" Yours very faithfully, 



" G. G. Anson. 



" The Marquis of Northampton, President of the Royal Society." 



The following description of the specimen referred to in the letter, 

 drawn up by John Lindley, Ph.D. F.R.S. , was also read: 



" Description of the Specimen referred to in the preceding letter." 

 By John Lindley, Ph. D., F.R.S. 



The plant which overran Lord Radnor's land is the Conferva crispa 

 of Dillwyn, which is said to be the Conferva fluviatilis of Linnseus. 

 The species inhabits fresh w^ater, and multiplies with great rapidity, 

 forming entangled strata. The green portion is the Conferva in its 

 young state, the white portion is the plant old and bleached. The 

 whole mass consists of articulated filaments, among which are frag- 

 ments of grass-leaves. 



The following papers were then read, or their titles announced : — 

 1. An Account of Experiments on the Reflecting Telescope. By 

 the Right Hon. Lord Oxmantowm, F.R.S. 



This paper enters minutely into the details of the experiments, of 

 the precautions requisite to ensure success, and of the manipulations 

 ultimately adopted in forming a speculum three feet in diameter, 

 subsequently applied to a telescope, mounted in a manner xery si- 

 milar to that of Sir John Herschel. The author states, as the re- 

 sults he arrived at, that S23ecula can be made to act eff^ectively, when 

 cast of the finest speculum metal, in separate portions, and retained in 



