1825.] Proceedings of Philosophical Societies. 59 



The author has given no figure of Gahn's blowpipe, which we 

 find superior to any other. Dr. WoUaston's, like all his inven- 

 tions, is perfect for the object proposed, viz. portability ; but for 

 constant use, one with a reservoir is preferable, and of those we 

 most ap])rove of the form given by Gahn. 



The article Hygrometer is one of the longest and best in the 

 book ; and we give the author credit for having dwelt amply on 

 the admirable instrument invented by Mr. Daniell. A wood- 

 cut, not very neatly executed, is given of this hygrometer, and 

 of Leslie's, as well as of some other apparatus. 



Under the head Hydrometer, Nicholson's useful table of the 

 correspondence of the degrees of Beaume's hydrometers for 

 salts and spirits, with their actual specific gravities at 55° Fahr, 

 is given, as well as Gilpin's valuable tables of the specific gra- 

 vities of alcohol of different strengths, and at different tempera- 

 tures. Under the article Measure Glass, also, several useful 

 tables are introduced, and generally through the work much 

 information, which both the student and proficient may refer to 

 with advantage. 



We are surprised that the author has not noticed the pyro- 

 meter invented by Mr. Daniell ; a long account is given of 

 Wedgwood's, which, it is now known, is an instrument of very 

 little service, since the clay pieces which serve to indicate the 

 temperature, contract as much by a lower degree of heat long- 

 continued, as they do by the most intense. We have also 

 looked in vain for a figure of Mr. Cooper's excellent apparatus 

 for the analysis of organic substances. Neither that nor Dr. 

 Front's are noticed. Hiatus valde defieiidus! However, on the 

 whole, we think the Explanatory Dictionary cannot fail to be 

 useful to a large class of chemical readers, and hoping the 

 author will fill up the desiderata in the next edition, we wish he 

 may soon have the opportunity of doing so, and bid him heartily 

 farewell. 



Article XII. 

 Proceedings of Philosophical Societies. 



KOYAL SOCIETY. 



The meetings of this learned body, as we have already men- 

 tioned, were resumed on the LSth of November, 1824; when 

 Douglas C. Clavering, Esq. Capt. R.N. was admitted a Fellow 

 of the Society, and the following communications were read : — • 

 The Croonian Lecture, by SirE. Home, VPRS. : — In pursuing 

 his researches in minute anatomy, the author stated, at the 

 commencement of this Lecture, he had again availed himself of 

 the skill and accuracy of Mr. Bauer ; and in this respect he 



