50 KIGHTH REPORT — 1838. 



tributed over that country ; forming the basis of a memoir on 

 the Scottish Isoclinal and Isodynamic lines, which was printed 

 in the fifth volume of the Association Reports, and published in 

 1837. 



In the same summer Professor Lloyd commenced the mag- 

 netic survey of England by a series of observations at fourteen 

 stations, principally in the midland and southern districts ; these- 

 observations have not been hitherto published, and will be found 

 in their place in the present memoir. 



The interest which had been excited at the meetings of the 

 British Association by the Irish and Scotch Magnetic Reports, 

 induced Professor Phillips to provide himself with an apparatus 

 for the dip and intensity ; having particularly in view the inves- 

 tigation of the influence which he deemed it possible the con- 

 figuration of the surface, or the geological character of the di- 

 strict, might have on the position or on the inflexions of the lines 

 representing these phagnomena. In the summer of 1837 Mr. 

 Phillips visited and observed at twenty-four stations in England, 

 chiefly in the northern district ; these observations arc now first 

 published. 



In the same summer Mr. Fox determined the dip at twenty 

 stations in the north of England and south of Scotland ; and in 

 the summer of 1838 at eight stations in the south of England, 

 extending from London to the Scilly islands ; at some of the 

 latter stations he also observed the intensity : these observa- 

 tions form part of the present memoir. 



In August 1837 Captain James Ross commenced a series of 

 magnetic observations, which he continued almost uninterrupt- 

 edly until the close of 1838; they extend over England, Ire- 

 land and Scotland generally, and comprehend fifty-eight sta- 

 tions. His observations of the dip and of the intensity are in- 

 cluded in the present memoir. 



Lastly, between August 1837 f»id October 1838, 1 have taken 

 advantage of an interval between military duties, to observe the 

 dip and intensity at twenty-two stations, distributed for the 

 most part round the coasts of England and Wales, and extended 

 into Ireland and Scotland for the purpose of accomplishing a 

 more complete connexion of the different series. 



It has been the wish of the four gentlemen connected with 

 me in this undertaking, that I should draw up the memoir of 

 what our joint labours have accomplished. Our observations 

 have been now carried over the whole extent of England, Ire- 

 land and Scotland ; and may be considered in their combination, 

 and by their extent, to obtain, in some measure, the character 

 of a national work ; presenting to the immediate requisitions of 



