84 ON THE USE AND OFFICES 



" of a tree, it there meets with cold enough to 

 " condense it into a liquor, as the vapour in' a 

 " still is known to do ; in this form it returns 

 " to the root down the vessels, which do the 

 " office of veins, lying between the wood and 

 " the inner bark, leaving, as it passeth by, such 

 " parts of the juices as the texture of the bark 

 " will receive and require for its support." 



Miller says, " The notion of the circulation 

 * was entertained by several authors much about 

 " the same time, without any communication 

 " one with another, particularly M. Major, a 

 " physician at Hamburgh, M. Peracett, Mari- 

 " otte, and Malpighi : it has met, however, with 

 " some considerable opposers, particularly the 

 " excellent M. Doddart, who could never be 

 " reconciled to it. 



" M. Doddart, instead of the same juices 

 " going and returning, contends for two several 

 " juices ; the one imbibed from the soil, digested 

 *"' in the root, and from thence transmitted to the 

 " extremes of the branches, for the nourishment 

 " of the plant ; the other received from the 

 " moisture of the air, entering in at the extremes 

 *'* of the branches; so that the ascending and 

 " descending juices are not the same." 



Mr. Knight is also an advocate for the doc- 

 trine of circulation, and has published a variety 



