82 MAGNETIC SURVEY OF TASMANIA. 



with observations made at a later date in other colonial 

 observatories, some important generalisations were 

 obtained by Sabine with regard to the magnetic pro- 

 blem in the southern hemisphere. 



It is a matter of regret that neither in the library of 

 this Society, nor in the public and parliamentary libraries 

 of Hobart, is to be found the official publication of either 

 the magnetic observations made by Lieut. Kay and his 

 colleagues in Hobart, or of Sabine's report thereon. In 

 this context it may not be out of place to state that in the 

 Hobart Observatory is a large accumulation — perhaps 

 60 or 70 volumes — of the actual records of observation 

 made by the meiribers of the Royal Society's expedition. 

 The scientific enthusiasm of the Government Astronomer, 

 Mr. Kingsmill, has rescued them from the decay into 

 which they were likely to speedily depart if left in the 

 condition in which he found them when he took posses- 

 sion of the observatory ; and, though they now rest in 

 the decent obscurity of a shelf in the observatory cellar, 

 this scarcely seems to be a suitable place of interment, 

 and I trust that this Society, as the leading scientific 

 body in Tasmania, may see its way to secure these records, 

 which are, so to speak, scientific heirlooms of the greatest 

 interest. 



I will now lay before the Society a brief resume of 

 the results obtained by Lieut. Kay and his party during 

 their prolonged stay in Hobart. In 1843 the mean 

 declination of Hobart was 9° 53' Vd" E., and between 

 this date and 1848 it increased to 10° 0' 37", giving a 

 total increase of 1' 18", or an annual increase of about 

 1' 27". During the period covered by Lieut. Kay's 

 observations the dip fell from 70° 42' 18' in 1842, to 

 70° 32' in 1845 : it then began to increase, and in 1848 

 it had attained the value of 70° 35' 42". The happy 

 accident that, during Lieut. Kay's stay in Hobart, the 

 dip passed through a minimum value, is a matter for 

 nauch congratulation. It is also of great interest to find 

 that, during the period under consideration, the mean 

 value of the horizontal intensity also passed through a 

 minimum value. This minimum value was reached, 

 not in 1845, when the dip was at a minimum, but three 

 years later — in 1848. An admirable account of the 

 instruments used by Lieut* Kay in his magnetic work in 



