VOL. XLIV.] PHILOSOPHICAL TRANSACTIONS. 327 



of our terrestrial time. Hence, as her annual motion is perfonned in about 

 225 of our days, it will contain 234 of hers ; consequently, to an eye placed in 

 Venus, the sun will always appear to go through a sign of the zodiac in IQ^- of 

 her days ; and as her axis has no inclination, she must have a continual equality 

 of her days and nights, without any variation of seasons, and so her annual mo- 

 tion can be of no other use than to keep her from falling down to the sun. 



But Bianchini gives a very different account of her ; which is, that her axis 

 inclines 75° from the plane of her ecliptic; and that her diurnal motion is per- 

 formed in 24 days and 8 hours of our time ; and this will cause her year, which 

 is equal to almost 225 of our days, to contain only Q^ of her days ; and this odd 

 quarter of a day in Venus will make every 4th year a leap-year to her, as happens 

 to us on earth, by the 6 hours that our year contains above 365 days : and to her 

 the sun will appear always to go through a sign of the zodiac in little more than 

 I- of her day, which is equal to 1 8-J- of our days ; and in going round the sun, 

 her north pole constantly leans towards the 20th degree of Aquarius. 



Thus, with regard to the absolute length of Venus's year, Bianchini agrees 

 with Cassini and other astronomers : but differs widely in other very remarkable 

 particulars, from which arise so many advantages, as to make that planet in- 

 comparably more fit for its inhabitants, than we could possibly conceive it to be 

 by a quick rotation on an axis perpendicular to its annual path. 



But, by such a motion as Bianchini describes, these inconveniences are 

 avoided ; for there is no place in Venus but what will have the 4 seasons every 

 year, and the heated places will have time to cool ; because, to any place over 

 which the sun passes vertically on any given day, he will, on the next day, be 

 26 degrees from its vertex, even though the place be on the tropic ; and if it be 

 on the equator, one day's declination will remove him 37-^ degrees from it. 



By passing a narrow slip of paper around the terrestrial globe, crossing the 



Mr. F. was born in Bamfshire 171O, of poor parents. He first learned to read, by overhearing his 

 father teach his elder brother ; and indeed all his knowledge afterwards was of his own acquisition. 

 He soon discovered a peculiar taste for mechanics, which first arose by seeing his father make use of 

 a lever. He pursued this study to considerable length, while he was yet very young ; and made a 

 watch in wood-work, from having once seen one. At a fit age he went to service with a farmer ; 

 when tending the sheep gave him leisure to make considerable advances in mechanical and astrono- 

 mical knowledge. He acquired also some skill in drawing j and going to Edinburgh, he there for 

 some time followed the profession of taking portraits in miniature, at a small price : an employment 

 by which he supported his family for several years, both in Scotland and England, while he pursued 

 more serious studies, and the labour of philosophical lectures. Mr. F. was a f.r.s. ; he died in 1776, 

 at 66 years of age. 



A full accoiuit of Mr. F.'s life was printed by himself, being prefixed to his Select Mechanical 

 Exercises. An abstract of which may be seen in Dr. Hutton's Mathematical and Philosophical Dic- 

 tionary, with a complete list of Mr F.'s separate publications; besides which, his numerous commu- 

 nications to the Royal Society are printed in the Philos. Trans, from vol. xliv. to vol. Ivii. inclusive. 



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