VOL. XIX.] 



PHILOSOPHICAL TRANSACTIONS. 



121 



-the frame of the microscope, without weakening its spring, and so become 

 more conveniently portable. 



At B is a hole, about ]-10th of an inch diameter, which serves to convey the 

 water in, when we have a mind lo see the minute objects or animals contained 

 in it, by having their images reflected from the opposite interior surface of the 

 drop, the frame of the microscope being held by the other end a, during the 

 observation ; for I find, that if the plate be of some thickness, the objects are 

 seen more distinctly than by only taking the water on a pin or wire, or the like; 

 besides, the water is now better secured, and one may with more ease give it 

 to others to observe, without so much danger of spoiling the spherical form 

 on which the distinctness of its objects depend. 



The best proportion for the hole at b is, to be somewhat less then half the 

 thickness of the metal in its diameter ; and to be so filled with water, till there 

 remain near a hemisphere of the water on each side the hole, and it will not be 

 amiss to have this end somewhat thicker than the other. 



An Account of the Quantities of Rain fallen in one Year in Gresham College, 

 London, per Month. N° 223, p. 357. 

 This was begun Monday morning, August 12, 1695, and the water weighed 

 every Monday morning till August 12, 1696, by pounds, ounces, and grains, 

 Troy Weight, the diameter of the vessel which receives the rain being 11-^ 

 inches, or '-rV part of an inch, and the area 102 -^^ inches. 

 Months Days ft 3 Gr. Months Days lb 5 Gr. Months Days ft 5 Gr. 



August I(), 2 6 216 December 23, 1 60 



26, 4 6 246 



September 2, 9 4 pf) 



9, 3 10 597 



16, 1 204 



23, 6' ;i36 



30, 4 1 444 



October 7, 2 3 06 



14, 2 60 

 21, 1 234 

 2S, 45 



November 4, 2ii7 



11, 1 11 65 



15, 1 I 309 



25, 9 285 



December 2, 8 126 



9, 3 7 324 



16, 1 3 435 



VOL. IV. 



30, 5 S 93 



January 6, 4 10 105 



13, 1 12 



20, 1 10 450 



27, 1 5 82 



February 3, 6 11 371 



10, 4 9 242 



17, 6 291 



24, 2 180 



March 2, 9 12 



9, 2 459 



16", 396 



23, 4 4 263 



30, 1 5 285 



April 6, 2 3 375 



13, 1 294 



20, 2 1 



H 



April 27, 7 390 

 May 4, 4 10 45 

 II, 7 6 

 18, 6 2 105 

 25, 1 7 60 

 June I, 99 

 8, 6 6 150 

 15, 2 120 

 22, 7 5 285 

 29, 1 5 8* 

 July 6, 1 120 

 13,16 1 

 20, 1 7 240 

 27, 6 1 256 

 August 3, 1 10 120 

 10, 1 11 90 

 12, 

 The sum 131 7 113 = to 29^'^ 

 inches in a cylinder of the aforesaid 

 diameter, viz. ll^*, inches. 



