228 PHILOSOPHICAL TRANSACTIONS. [aNNO ] 746. 



equator in 2 opposite points at an angle of 75°, it would, by representing Venus's 

 ecliptic drawn on her globe, serve for the solution of problems concerning her, as 

 the ecliptic on our terrestrial globe does for those relating to our earth. 



Things being thus premised in general, Mr. F. proceeds to give a description 

 of the particular phenomena in Venus, confining himself chiefly to what happens 

 in her northern hemisphere ; knowing that the same must happen, mutatis mu- 

 tandis, in the southern. 



1 . Her axis is inclined 51^ degrees more than the axis of our earth, and there- 

 fore the variation of her seasons will be much greater than of ours. 2. Because 

 her north pole inclines towards Aquarius, and ours to Cancer ; her northern parts 

 will have summer m the signs where those of our earth have winter ; and vice 

 versa. 3. The artificial day at each of her poles (containing 4-|- apparent diurnal 

 revolutions of the sun) will be equal to 1 12-l natural days on our earth. 4. The 

 sun's greatest declination, on each side of her equator, amounts to 75°: therefore 

 her tropics are only 15° from her poles, and her polar circles at the same distance 

 from her equator. Consequently, her tropics are between her polar circles and 

 poles, contrary to what those on our earth are. 6. The sun, in one apparent 

 diurnal revolution from the equator, and any meridian where he crosses it, to the 

 same meridian again, changes his declination at least 14° more on Venus, than 

 on our earth from the equinox to the solstice. 



Mr. Ferguson then pursues his speculations on the phenomena of the planet 

 Venus, relative to the more minute particulars ; such as the sun's rising and 

 setting, the days and nights, &c. ; which being matters of mere curiosity and 

 speculation, it is of no use now to pursue them further ; especially also as such 

 phenomena are similar to the like circumstances on our earth, but differing only 

 in their degree. 



^ Machine for Sounding the Sea at any Depth, or in any Part. Invented hy 

 Major ff^lliam Cock in the Tear 1738, in a Foyage to Georgia. N''479, 

 p. 146. 



The draught of this machine is exhibited in fig. 1, pi. 5 ; where aaaa repre- 

 sent a trunk of timber, with a square hollow, through the centre of which passes 

 the square piece of timber bb ; having a groove on each side, in which are placed 

 the two pieces of iron cc ; the foot of each resting on the pins dd, that pass 

 through the trunk ; the upper part of the irons are hooked to an iron pin at e, 

 which passes through the square piece bb ; which piece is hollowed for the hooks 

 of the irons cc to pass up and down. 



When the weight f touches the ground, the two irons cc sink the trunk 

 down, which unhooks them at e ; on which they fall off, and leave the trunk at 

 liberty to float or rise up again to the surface. A machine of these dimensions^ 



