498 Mr. John Hogg's Specimen of a 



body can never be concentrated on any one solid body. 

 Amongst other facts of which we are instructed by this theo- 

 retical conclusion, we learn why the electrical condition of 

 the uninsulated Leyden coating can never become so highly 

 intense as the opposite coating to which the charge is directly 

 communicated. 



What has been said may suffice to explain that the prin- 

 ciple of compensation is one of the necessary consequences 

 of the definite nature of the major electrical attraction ; but 

 the evidences are far from being exhausted. I have* in this 

 paper endeavoured, and shall continue in those which are to 

 follow, to test the new theory when ^Practicable by reference 

 to experiments already known and by facts generally ac- 

 knowledged ; rather than to adopt others that might, perhaps, 

 have been regarded as partial in their applicability or com- 

 plicated in their conditions. 



London, April 17, 1838. 



[To be continued.] 



LXXVII. Specimen of a Thermometrical Diary kejjt abroad 

 in the Years 1824, 1825, and 1826; and compared nsoith a 

 corresponding one made in London during the like Period, 

 By John Hogg, Esq,, M.A., F.C.P.S., M.KG.S., ^c. 

 Fellow of St, Peter^s College, and late one of the Travelling 

 Bachelors, in the University of Cambridge, 



To the Editors of the Philosophical Magazine and Journal, 

 Gentlemen, 

 nPHE following specimen of a diary of observations made 



-■- with the external thermometer, graduated on the scale 

 of Fahrenheit, during an excursion on the continent in the 

 summer of 1824, and also during more extensive travels 

 abroad in the years 1825 and 1826, I now beg to oifer you, 

 even after such a lapse of time as twelve or fourteen years, 

 for the purpose of impressing upon future travellers, if not 

 the necessity of making similar observations, at least that a 

 great degree of utility and interest may be attainable to sci- 

 ence, by keeping careful diurnal registers of the temperature 

 of the atmosphere during their absence from England, so that 

 upon their return home they may compare them with observa- 

 tions taken in England during those identical days. 



I have only thought it necessary to insert in this specimen ; 

 a very small portion of my Diary, — indeed, just sufficient to 

 enable your readers to see the manner I adopted of enter- 



