VOL. XIII.J PHILOSOPHICAL TRANSACTIONS. 655 



would be, which is very remarkable. For this very reason I made use of very 

 strong vinegar, dephlegmed by freezing; by this mixture we came much nearer 

 the freezing point. But since it proves troublesome to prepare this vinegar, 

 and because it can be done only at certain times, I have most commonly made 

 the experiment with spirit of venus, or verdigrise, which is the highest vinegar 

 in the world: with this the cold will be most sensible to the touch, and most 

 conspicuous on the weather glass (thermometer.) For by this mixture I have 

 in summer made a weather glass (thermometer) to descend below the tempera- 

 ment of cold fountain water, six inches at least, which brought it so near the 

 freezing mark, that it scarcely wanted half an inch.* But at the same time 

 the liquor swells and takes up more room than before, and will not be contained 

 in shallow vessels. In this experiment we have some things very rare, that a 

 great and violent motion of two dissenting liquors should be so far from pro- 

 ducing heat as to produce a notable degree of cold, and that too with a consider- 

 able expansion of their parts. Here we might instance in an apposite and as 

 unexpected an experiment, where an effect contrary to our common observation 

 happens; and that is thus, if you mix with oil of vitriol a quantity of water, 

 a great heat will follow, without an expansion of these liquors. 



The Anatomy of Plants : with an Idea of a Philosophical History of Plants : 



and several other Lectures, read before the Royal Society. By Nehemiah Grew, 



M. D. F. R. S. and of the Coll. of Physicians, 1082. N° 150, p. 303. 



This work, which was begun about IQ years ago, has been carried on 



by the special appointment of the Royal Society; and by their order is now 



made public. 



The idea prefixed to the anatomy gives us an account of the materials and 

 methods necessary for making a complete history of plants; which are copiously 

 proposed under these five general heads of inquiry, viz. 1. Of those things 

 which are of more external consideration about plants ; as their figures, &c. 

 2. Of their compounding parts; as vessels, &c. 3. Of their liquors and other 

 contents. 4. Of their principles; as salts, &c. 5. Of their aliment; as water 

 and other means of growth. Aiming chiefly at the discovery of the reason of 

 vegetation, and of the virtues of plants. The anatomy is divided into 4 books. 

 In the first, all the observations, except one or two, are made with the naked 

 eye : in order that a proof might first be given, how far it is possible for us to 

 go without the help of glasses, which many ingenious men want; and more, 

 the patience to manage them. It begins with the seed sown, and so proceeds 



* The author's attempt to apply this experiment to the explanation of the cold and hot fit of an 

 ague, is in the highest degree unphilosophical, and is for that reason omitted in this abridgment. 



