THE VICTORIAN ERA 181 
needle pointed with its north-seeking end vertically down- 
wards. The Rev. Prof. Humphry Lloyd, of Dublin, had 
perfected instruments for magnetic observations and made 
many important researches on these subjects. All three 
were associated on one of the British Association com- 
mittees, the work of which consisted of making a mag- 
netic survey of the British Isles between 1833 and 1837, 
proceeding on the sound policy of beginning at home. 
At the same time in 1835 Sabine presented to the Asso- 
ciation a full abstract of Hansteen’s “ Magnetism of the 
Earth.” Two years previously, Mr. S. Hunter Christie, 
of Cambridge, in a survey of the existing views as to 
the magnetic theory had introduced for the first time to 
most British readers the name of a German mathematical 
physicist, Johann Karl Friedrich Gauss, who held 
original views on terrestrial magnetism, as to which the 
Cambridge don pronounced an opinion so guarded that 
whether the views in question were ultimately approved 
or buried in oblivion, his judgment would appear to have 
been justified by the event. 
In 1823 Johann Kaspar Horner, who had sailed round 
the world with Krusenstern as magnetic and meteoro- 
logical observer, revised and greatly improved a map by 
the Swedish investigator Wilcke showing lines of equal 
magnetic dip for the whole Earth so far as observations 
went. This made it possible for Sabine to present to 
the British Association a Report of epoch-making im- 
portance on the Distribution of Magnetic Intensity. 
The fact that the total intensity of magnetic force varied 
from place to place had been known for some time, but 
until Sabine’s experienced eye had inspected and dis- 
cussed the records no systematic attempt had been made 
to place these variations on a chart. 
