of the Scientific Memoirs. 83 



Prof. LowiG, Experiments on the Essential Oil of the Spircea Ulmaria, 

 or Meadow Sweet. (From Poggendorff's Annalen.) 



Baron Walckenaer, Researches relative to the Insects known to the An- 

 cients and Moderns by which the Vine is infested, and on the Means 

 of preventing their Ravages. (From the Annales de la SocUte Entomo- 

 logique de France.) 



Dr. Carus, The Kingdoms of Nature, their Life and Affinity. (From 

 the Zeitschrift fiir Natur und Heilkunde.) 



J. A. Balard, Researches concerning the Nature of the Bleaching Com- 

 pounds of Chlorine. (From the Annales de Chimie et de Physique.) 



E. Lenz, On the Laws of the Conducting Powers of Wires of different 

 Lengths and Diameters for Electricity. (From the Memoirs of the 

 Academy of Sciences of St. Petersburg.) 



Among the^e it will be seen that the entire series of Mel- 

 loni's important investigations are now first given to the 

 English public. In order to render the work useful and in- 

 teresting, I have been advised to give a preference to subjects 

 which engage immediate attention in this country. Of this 

 kind are the labours of M. Becquerel upon the artificial pro- 

 duction of crystallized minerals by means of voltaic action. 

 The communications of Mr. Fox and Mr. Crosse at the late 

 meeting of the British Association at Bristol have excited 

 much interest upon this subject^ at the time and subsequently. 

 (See pp. 228 and 537 of o^^i* preceding volume.) What had 

 been done by Becquerel with regard to it appears^ however, 

 to have been unknown both to those gentlemen and a great 

 part of their auditors, the only accounts of his experiments 

 that had appeared in this country being our short notice in 

 1830, (Philosophical Magazine and Annals, vol. xii. p. 226,) 

 and that in Mr. Whewell's Report on Mineralogy. In pre- 

 paring for publication M. BecquereFs paper I have beei\, fa- 

 voured with the valuable assistance of Mr. Brooke and Mr. 

 Golding Bird : and for the highly important Memoir by 

 Mossotti I am indebted to Prof. Faraday, who kindly com- 

 municated to me a copy which he had just received from the 

 author. These occupy a portion of the Third Part; together 

 with the two entire Memoirs of Ehrenberg on his discoveries 

 of Fossil Infiisoina, which are just now engaging much of 

 the attention of naturalists. Two additional papers by Melloni 

 are now given, in one of which he describes his mode of se- 

 parating the rays of light from those of heat. The insertion 

 of Von Wrede's Memoir on the absorption of light was oblig- 

 ingly suggested to me by Professor Powell. 



List of the Memoirs contained in Part III., just published : 



M. Clapeyron, On the Motive Power of Heat. (From the Journal de 



VEcole Royale Poly technique.) 

 Dr. BuRMEisTER, On the Sound produced by Insects in Flying. (From 



Poggendorff's Aniialen.) 

 M- Melloni, On the Reflection of Radiant Heat; and. 



On the Theory of the Identity of the Agents which produce Light and 

 Radiant Heat. (From the Annates de Chimie et de Physique.) 



M2 



