642 PHILOSOPHICAL TRANSACTIONS. [aNNO 17 11. 



malcula, for one that I saw at 5 o'clock. : for between 12 and 5 o'clock I had 

 made 25 several observations, and those almost always by making new incisions 

 with a knife into the testes, and by squeezing the matter out of the incision, 

 though no larger than a pin's head. 



Now while these animalcula were swimming in the fluid matter, 1 observed 

 often through the microscope, that the first part of their bodies gave a very 

 bright glance; just as we see in small fishes swimming in the water, when they 

 turn on their sides or bellies, and cast a glittering brightness to the eye : from 

 which I imagined, that the upper part of the small bodies of the animalcula in 

 semine masculino of the rams, were flattish, and that the brightness proceeded 

 from their exposing those flattish sides to the sight in swimming. The next 

 morning at 7 o'clock, I viewed the matter of the second testicle, which I had 

 bound up in a cloth, with my microscope; but I could not perceive any thing 

 that had the least life in it; and the testicle had begun to spoil, having a bad 

 smell. 



Now since we perceive that the animalcula, in the testes of a ram, can live 

 32 hours after the ram is dead, we may very well conclude, that the said ani- 

 malcula in semine masculino of a ram, being admitted into that part of the 

 uterus of the ewe, called tuba Fallopiana, will live much longer, that being the 

 place which nature has provided for them. From whence it may follow, that 

 after the copulation of the male and female, the animalcula may be 2 or 3 days 

 in coming into that part of the uterus, where they receive their nourishment, 

 and consequently before the female is impregnated. And the same may be ap- 

 plied to other animals. 



An Account of a Lunar Rainbow seen in Derbyshire, and of a Storm of Thunder 

 and Lightning ivhich happened near Leeds in Yorkshire. By Mr. Ralph 

 Thoresby, F. R. S. N° 331, p. 320. 



The iris lunaris being so rarely seen, that Dr. Plot tells us (Nat. Hist, of 

 Oxford, cap. 1 , § 7,) that several learned and observing men never saw one in 

 their lives, and that even Aristotle himself observed only two in above 50 years; 

 the ensuing account, which I had from a gentleman of great veracity and in- 

 genuity, will be the more acceptable. He was lately in Derbyshire, where, on 

 Christmas last, he was at Glapwell Hall ; and walking towards Patterton-Green, 

 about 8 in the evening, he observed with great satisfaction the bow, which the 

 moon had fixed in the clouds: she had then passed her full about 24 hours; 

 the evening had been rainy, but the clouds were dispersed, and the moon shone 

 pretty clear. This iris was more remarkable than that which Dr. Plot observed 

 at Oxford, the 23d of November 1675, that being only of a white colour, but 



