INDEX. 
P P a g e 
Parallactic machine , remarks on an instrument so called, - 73 
Placenta , remarks on its vessels, - - 160 
Porous vessels , their use in making ice, - 57 
experiments on the effect of the evaporation pro- 
duced from them, - - - 129 
Presents received by the Royal Society, from November 1792 to 
June 1793, - - - - - 229 
Production, extraordinary, of human generation, - 154 
Projection table, remarks on an instrument so called, - 215 
Q 
Quadrant of stone, in the observatory at Benares, described, - 46 
Quadrupeds, experiments on, - - 23, 25, 27 
Queries , optical , attempt to solve some, - - 1 7 8 
R 
Rain in Rutland, Surrey, and Hampshire, register of, - 220 
comparative tables of, - - 223 
Rainbows, account of two, seen at the same time, 1 
Ramsden, Mr. Jesse, description of an instrument made by him, 75 
Rennell, James, Esq. Observations on a current that often 
prevails to the westward of Scilly ; endangering the safety of 
ships that approach the British Channel, - 182 
Rhinoceros, double horned, of Sumatra, description of 3 
S 
Saturn, remarks on some appearances said to have been seen in 
that planet, - - - 202 
Schmeisser, John Godfrey. Description of an instrument for 
ascertaining the specific gravities of fluids, - - 164 
Scilly, observations on a current that often prevails to the west- 
ward of, - - - - -182 
remarks on the light-house there, - - 198 
Short, Air. Janies, first applied -a telescope to a combination of 
circles, - - - _ -71 
Shuckburgh, Sir George, Bart. An account of the equatorial 
instrument, - - - -67 
Smeaton,Mr . account of an experiment made by him, - 185 
2 I 
MDCCXCIII. 
