Notices respecting New Books. 75 



The optical principle on which this instrument W con- 

 structed seems to merit move attention than I have hitherto 

 been able to pay to it ; and in the instrument itself there is 

 still room for further improvements. 

 I am, Sir, 



Your humble Servant, 



Ez. Walker. 



XV. Notices respecting New Books. 



Philosophical Transactions of the Royal Society of London, 

 for the Year 1806. Part I. 



This part contains:— 1. The Croonian Lecture on the 

 Arrangement and mechanical Action of the Muscles of 



Fishes. Bv Anthony Carlisle, Esq. F.R.S. F.L.S. 



2. The Bakerian Lecture on the Force of Percussion. By 

 William Hyde Wollaston, M.D. Sec. R.S.-3. Memoue 

 sur les Ouantites imaginaires. Par M. Bu6e.-4. Chemical 

 Experiments on Guaiacum. By Mr. William Brande:— 

 5. On the Direction of the Radicle and Germen during the 

 Vegetation of Seeds. By Thomas Andrew Knight, Esq. 

 F.R.S. In a Letter (o tin- Right lion. Sir Joseph Banks, 

 K.B. P.R.S.— 6. A third Series of Experiments on an ar- 

 tificial Substance which possesses the principal characteristic 

 Properties of Tartnin j with some Remarks on Coal. By 

 Charles Hatchett, Esq. F.R.S.-/. The Application of * 

 Method of Differences to the Species of Series whose Sums 

 are obtained hv Mr. Landen by the Help of impossible 

 Quantities. By Mr. Benjamin Gompertz. -8. An Account 

 of a small Lobe of the human prosiate Gland, which has 

 not before been taken notice of by Anatomists. By Eve- 

 rardllome, Esq. F.R.S.-Q. On the Quantity and Velo- 

 city of the Solar Motion. By William Herschel, LL.D. 



F.R.S. 



Appendix.— Meteorological Journal kept at the Aj - 

 mentfl of the RoyaJ Society, by Order of the President 1 

 Council . 



