38 



in the computation. No hypothesis is introduced into the process, 

 and therefore no correction of error by trial is requisite. 



Of three methods proposed, one combines the advantages of Keill's 

 series and Cassini's approximation together, and is regarded by the 

 author as the most simple in theory, and most expeditious in prac- 

 tice, which has yet been proposed. 



Demonstrations of the late Dr. Maskelyne's Formulae for finding the 

 Longitude and Latitude of a celestial Object from its Right Ascension 

 and Declination ; and for finding its Right Ascension and Declination 

 from its Longitude and Latitude, the obliquity of the Ecliptic being 

 given in both cases. By the Rev. Abram Robertson, D.D. F.R.S. 

 Savilian Professor of Astronomy in the University of Oxford, and 

 Radcliffian Observer. Communicated by the Right Hon. Sir Joseph 

 Banks, Bart. G.C.B. P.R.S. Read February 15, 1816. [PAtY. 

 Trans. 1816,^. 138.] 



Dr. Robertson conceives that no full demonstration of these for- 

 mulae has yet been published; and hence no one has hitherto remarked 

 two oversights with respect to their application to certain particular 

 cases, which had escaped the notice of their author. Their value, 

 however, has been duly appreciated by those most competent to 

 judge of their merit, especially by M. Delambre, who remarks upon 

 their conciseness, as well as precision, in comparison even with the 

 formulae given by Lalande. 



Some Account of the Feet of those Animals whose progressive Motion 

 can be carried on in opposition to Gravity. By Sir Everard Home, 

 Bart. V.P.R.S. Read February 22, 1816. \Phil. Trans. 1816, 

 p. 149.] 



The power which flies have of crawling upon a ceiling is well 

 known, but the mode in which this is effected, says the author, has 

 never been explained. It was not till lately he learned that there 

 are animals of a larger size which have the same power, and in which, 

 from their size, the construction of their feet will admit of more ac- 

 curate examination. 



The Lacerta Gecko of Java walks up and down the smoothly po- 

 lished chinam walls in quest of flies, and runs upwards to its retreat 

 in the roofs of the houses, although the weight of a specimen given 

 to the author by Sir Joseph Banks was as much as 5|- ounces. 



On the feet of this animal are five toes, armed with a very sharp 

 and curved claw ; and there are also on each sixteen transverse slits, 

 with serrated edges, with pouches between them, which are consi- 

 dered by the author as the striking peculiarity in the foot of this 

 lizard. When these are closed, the under surface of the foot bears 

 a considerable resemblance to the upper part of the head of the 

 sucking fish, the surface of which is furnished with two rows of 

 moveable plates attached by one edge, and serrated at the other, and 



