cf fever al Species of Pi, lien, 69 



faturated with moifture, (or has loft, by keeping, a part of its irri- 

 tability?) but it does not enter the dry grains ib readily as water 

 alone. 



1 have fince fubjedled pollen to examination in fcvcral of the 

 mofl ftimulant oily and lalinc liquids, but have not been able to 

 perceive that any of them had a fimilar cfFe6t on it. 



It is piopcr here to remark that the utmoft care is reqnifite to 

 prevent accidental mixtures of the fubje6\s or menftrua in thefe ex- 

 periments, which might greatly embarrafs and miflcad the oblerver. 

 Separate pieces of clear glafs for the feveral kinds, and feparate pointed 

 glafs tubes to convey the liquids, will therefore be requifite. It will 

 be proper attentively to examine the pollen dry, as well as the 

 liquids, before they are ufed, in order to be fatisfied of the abfcnce 

 of animalcules and other extraneous matters which might be fuf- 

 pe6led to influence the appearances. 



I do not pretend to fay that the above-related experiments were 

 abfolutely free from optical deception ; but I may venture to affirm, 

 from frequent repetition of them, that, when tried with due pre- 

 caution, they will fcajcely ever be found to fail of ]^roducing the 

 appearances related. 



Engagements of fuperior importance at prefent prevent, and may 

 long continue to prevent, my pufhing thefe inquiries much further. 

 It is lor this reafon, and becaufe I fhould take a pleafure in feeing it 

 done by fome perfon more capable of executing them with due ex- 

 a6lnefs, and drawing proper inferences from them, that I am willing 

 to make them known in their prefent imperfe6l ftate. For the 

 affifiiance of thofe who may incline to profecute the fubie6l, I fhall 

 now ll ate the amount of the prefent difcovery, and the hints for 

 further inveftigation which have occurred to me. 



Should it be found, on repeating and extending thefe obferva- 



tion s, 



