Royal Society. 501 



phenomenon, of which he proposes to give a new one, and points 

 out various courses which the propelled air may be supposed to 

 to taiie with reference to the cards. He then offers what he con- 

 siders to be the true explanation of the phenomenon. He con- 

 eiders that no sooner has the air struck upou the loose card, than it 

 is reflected, spreading partly, if uot entirely, over its surface, and 

 then ascends, carrying with it the interposing atmosphere, and ex- 

 cluding the surrounding air. This, he submits, is analogous to ordi- 

 nary suction, and by this means the loose card is at once drawn 

 up and fixed. He considers that the reflected air, thus rising and 

 driven out by the descending current, will have additional power 

 when the fixed card is considerably larger than the other. 



2. " On the relation of the Direction of the Wind to the Age of 

 the Moon, as inferred from observations at the Royal Observatory, 

 Greenwich, from ISiO November to 184-7 December." By G. B. 

 Airy, Esq., F.R.S. &c.. Astronomer Royal. Received January 9, 

 1851. 



The author states, that in a voyage to Shetland, in the year 1849, 

 he heard allusions to the belief entertained generally by Norwegian 

 seamen, that a northerly wind may always be expected about the 

 time of new moon. The expression of this belief was so positive, 

 and the implication of the interests of the persons entertaining it 

 was 80 distinct, that it appeared to him extremely probable that 

 there was some physical foundation for it. At the first convenient 

 opportunity he therefore took measures for discussing, with refer- 

 ence to this question, the directions of the wind at the Royal Ob- 

 servatory, during a period of rather more than seven years, as ascer- 

 tained from the records of Osier's self-registering anemometer. 

 He extended the research so far as to enable any one to judge 

 whether there is any probable relation between any direction of 

 wind and any age of the moon. 



The collection and summation of the numbers was effected under 

 the immediate superintendence of Mr. Glaisher; and great pains 

 were taken to establish such checks on the operation that error is 

 considered to be almost impossible. 



The general result is contained in a table subjoined to the paper. 

 This exhibits the number of hours during which the wind blew in 

 each of sixteen equal divisions of the azimuthal circle, and also the 

 number of hours of sensible calm, in the period extending (with 

 very small interruptions) from 1840 November to 1847 December, 

 arranged in reference to the days of the moon's age. The author 

 remarks, that while this table shows that there is great uncertainty 

 in the verification of an empirical law, even from nearly ninety luna- 

 tions, it seems very distinctly to negative tlie asserted law which 

 gave rise to the inquiry. 



March 13. — Lieut.-Col. Sabine, V.P. and Treasurer, in the Chair. 



The following papers were read : — 



1 . "On the Meteorology of the Lake District, including the results 

 of experiments on the fall of Rain at various heights up to 3166 feet 



