XXX Annual Report of the Council. 



for much of the present knowledge of vertebrate and invertebrate 

 zoology. But greater than his writings or his influence was the 

 dominant character of the man himself. A short autobiography 

 appeared in 1901. Y. W. G, 



Samuel Pierpont Langley, who has been one of our 

 honorary members since 1887, died on February 27th, 1906, at 

 the age of 72, while still in possession of all his faculties. A brief 

 mention of the more important of his contributions to scientific 

 literature is all that can be attempted within the limits at disposal. 

 By the invention of the bolometer he was enabled to study the 

 heat radiation from point to point of the sun's disc, to estimate 

 anew the constant of solar radiation, and to map out the solar 

 spectrum on the infra-red side, as far as "76/^. More recently the 

 investigation has been continued at the Allegheny Observatory, 

 under his direction, and with an improved form of the instru- 

 ment, to a still lower limit, ■37/x. The discovery that there are 

 considerable gaps in this portion of the spectrum, due to atmos- 

 pheric absorption, is likely to prove of service to meteorologists. 

 As an observer and delineator of solar phenomena, Langley has 

 probably never been surpassed, while his determination of the 

 moon's temperature is a model of patient work carried out under 

 most baffling conditions. To the problem of aerial flight he 

 also gave much attention, and his aerodrome doubtless embodies 

 the principles upon which, if ever, the true conquest of the air 

 will be achieved. In addition to the highest experimental skill 

 and ingenuity, Langley possessed in an unusual degree the 

 qualities of an organiser and administrator, the foundation of 

 the Smithsonian Aslrophysical Observatory, and of the National 

 Zoological Park being entirely due to his efforts, and his eighteen 

 years secretaryship of the Smithsonian Institution testifies still 

 further to his many-sided vigour. C. L. B. 



Robert Rawson was born at Brinsley, Nottinghamshire, 

 July 22nd, 1814. Up to the age of 23 he worked as a miner, 

 but having acquired a good knowledge of mathematics he then 



