Terrestrial Magnetism. 135 
investigating the properties of the magnet?—for how 
little could they anticipate that this humble mineral was 
destined hereafter to change the very form and condition 
of human society in every quarter of the globe. Before 
its properties were known, the ocean, which is now the 
high road of nations, was a fearful and trackless abyss, 
and voyages were confined to tedious and timid excur¬ 
sions on its shores. The wanderings of Ulysses, which 
took ten years to accomplish, did not much exceed in 
extent a journey from Hobart to Launceston. But when 
magnetic polarity was applied to the aid of navigation, 
mankind appear to have acquired a new sense : guided by 
its mysterious power Vasco de Gama doubled the Cape of 
Good Hope, Abel Tasman discovered the beautiful 
island we now inhabit, and the immortal Columbus led 
the way to the eastern and western world, giving a fresh 
impulse to the human mind which had before been 
comparatively slumbering for centuries. There is not a 
country inhabited by man that has not felt the influence 
of the discovery: it has been the parent of our naval 
and of our commercial greatness, and has thus greatly 
assisted in obtaining for us the commanding rank we now 
hold amongst the nations of Europe; and its unerring 
properties may almost be said to have done more in the 
civilization of the globe than any blessing that has been 
conferred upon the human race. 
A description of the instruments employed in the 
magnetic observatory will form the subject of a sub¬ 
sequent paper. 
