l6 PHILOSOPHICAL TRANSACTIONS. [anNO 1705. 



this were supposed by an astronomer in Venus it would be the Ptolemaic system, 

 in which the sun is carried round Venus, placed in the centre of all the planets 

 orbits, and such of the planets move in an epicicle similar and equal, but in a 

 contrary position, to the true orbit of Venus round the sun, the centres of the 

 epicicles being moved in their deferents in the same times that the planets them- 

 selves perform their revolutions in the true system. And a Ptolemaic system 

 made in this manner, would satisfy all the celestial phaenomena, equally as 

 well as the Tychonic or the true system ; so that if the Ptolemaic system for the 

 earth had been thus framed, there could have been no arguments from obser- 

 vations brought against it ; nor indeed any other way left to convict it of 

 falshood, but that only which is drawn from the principles of natural phi- 

 losophy. 



An Abstract of Dr. Mead's Mechanical Account of Poisons. Communicated by 

 Samuel Mor land. N° 283, p. 1320. 



Every medical reader is so familiarly acquainted with Dr. Mead's writings, 

 that the reprinting of this extract is judged to be wholly unnecessary. The 

 facts relative to the structure of the viper's teeth, the situation of the bags con- 

 taining the poison, and the manner of its infusion into the wound during the 

 bite, have been already mentioned in the notes on Redi's obsen'ations on this 

 subject, at p. 58, vol. i. of this Abridgment. It is only further necessary in 

 this place to remark, that Dr. Mead's mechanical hypothesis of the manner in 

 which he supposed the viperine and other poisons to act, is now exploded ; a 

 chemical explanation having been adopted in its stead. 



Concerning a fVater Spout^ lately observed at Hatfield. By the Rev. Mr. Abr, 

 De la Pryme, F. R. S. N" 284, p. 1331. 



The weather in this part of the country has been exceedingly wet and cool, so 

 that it seemed to be spring rather than midsummer, yet June 21, 1702, was 

 pretty warm, on the afternoon of which day, about 2 o'clock, no wind stirring 

 below, though it was somewhat great in the air, the clouds began to be much 

 agitated and driven together; on which they became very black, and were very 

 visibly hurried round, from whence there proceeded a most audible whirling 

 noise, like that commonly heard in a mill. After a while a long tube or spout 

 came down from the centre of the congregated clouds, in which was a swift 

 spiral motion like that of a screw, or the cochlea Archimedis when it is in mo- 

 tion, by which spiral nature and swift turning, water ascends up into the one, 

 as well as into the other. It proceeded slowly from west to north east, broke 



