VOL. X.] PHILOSOPHICAL TRANSACTIONS. 257 



shape of a tree. 6. The motions of trunks; where occurs the cause of their 

 ascent and descent into the ground ; their horizontal and spiral motion ; and 

 whence solar and lunar plants are distinguished ; some winding together with the 

 sun in its diurnal motion, by south from east to west ; and others with the 

 moon in its monthly motion, from west to east. 7 • The nature of trunks, as 

 variously fitted for mechanical use ; where he shows why woods are soft, hard, 

 clevesome, tough, or durable; why the heart of timber is most durable; and 

 why some trees have heart, and others not; likewise, whence the toughness of 

 flax, and what sorts of plants serve for the best tow ; giving lastly an account 

 how all prosperous conjunctions in grafting may be known, and what is the 

 chief use of grafting, viz. to accelerate the growth of good fruit. 



III. The Royal Almanack, &c. by N. Stevenson, one of his Majesty's 

 gunners. 



A continuation of the same almanack as publisheii the former year, and be- 

 fore described. 



Continuation of the Pneumatical Experiments, made by M. Huygens and M, 



Papin. ]SI°121, p. 492. 



To know whether the vacuum would be of use to the preservation of bodies, 

 an apple was inclosed, which had a little speck of rottenness, with some water in 

 the same recipient, thereby to promote its corruption in case any should take 

 place. But no change of that nature was observed. 



The 7th of June were inclosed in a receiver two nosegays of roses, one sus- 

 pended at the top, the other having its tail in a little vessel full of water, 

 together with a gauge 4 inches long, to know whether any air would be there 

 produced. Two days after, the roses were a little withered, and the water al- 

 ready risen to 8 or 10 lines, near the top of the gauge ; and after that, the 

 changes of these flowers became still less, so as not to be much more withered. 

 The roses in the water were as much withered as the others, and as soon. 

 I shall keep them in this condition as long as I can. Other roses which had 

 been included at the same time, but with air, grew mouldy in less than 3 

 days. 



At another time was inclosed one single rose-bud in a very small glass, to 

 discover whether it would keep its scent. At the end of 15 days it looked a 

 little less fresh, but was not at all withered ; and having taken it out, it had still 

 its good smell; but afterwards it lost all, both colour and smell, in less than two 

 hours. Its leaves did not appear moist in the vacuum, though they did so as 

 soon as they were in the air. Which shows, that the leaves had acted as 

 gp'onges, discharging their humidity by the pressure of the air. Some gilli- 



VOL. II. L L 



