82 CORRESPONDENCE OF RAY. 



ing. If your lady think it worth her perusal, and can be 

 content to bestow upon it some shreds of spare time, 

 the author takes that esteem of it to proceed from her 

 partiality to her husband's friend, rather than the merit 

 of the work. However, I pray present my very humble 

 service to her, and tell her I wish that I had something 

 to present her might be worthy her acceptance. Those 

 experiments of Dr. Hulse and Mr. Fisher about the acid 

 juice of pismires, I myself sent to Mr. Oldenburgh to be 

 communicated to the Royal Society. 



Middleton, March 3, 1670. 



Dr. Lister to Mr. Ray. 



Dear Friend, — You have most ingeniously given the 

 reason of that experiment I sent Mr. Oldenburgh, con- 

 cerning the not bleeding of entire twigs, which I did 

 after find to be the air only ; the posture 1 held them in, 

 that hindered their bleeding ; for, if I cut a twig with my 

 penknife, and held it up awhile, and then pei-^jendicularly, 

 it would not bleed ; yet, if it were then topped, it would 

 in some time show moisture, yet not always ; but the 

 bough from whence it was taken did constantly bleed, 

 and that immediately, in case it was a bleeding time. 

 And here I must observe to you one circumstance, that 

 the trees I wounded at Nottingham did bleed from the 

 same wounds five months together; but then these wounds 

 were next a brick wall, and not exposed to the air : on 

 the contrary, the trees I wounded here the beginning of 

 November have never bled from those wounds then made, 

 but from fresh ones many times. And this neglect in not 

 making new wounds certainly was the reason of the dif- 

 ference, or not bleeding of these York trees when yours 

 did in autumn. 



Feb. 21. — I made many experiments upon trees by 

 bringing them to the fire-side, and did discover many 



