8 
will each still point north and south. But who can account for the 
marvellous law of nature which causes these phenomena ? 
In the words of Dr. Hopkinson, in his recent interesting address 
before the Society of Electrical Engineers, ‘“‘ The more we know of 
magnetism the more remarkable does it appear. We know that °* 
iron, cobalt, and nickel are exceptionally magnetic metals, but no 
explanation has yet been offered as to why they possess a property 
which is, comparatively found nowhere else in Nature.” Another 
remarkable feature in these metals is the non-continuity of this 
magnetic property. For instance, a galvanometer needle connected 
with an iron ring (the temperature of which latter may be heated 
to 770 deg. cent.) attains a deflection eleven thousand times as 
great as it the ring were of copper or glass. But if the tempera- 
ture rises yet another 15 deg., the value of the deflection suddenly 
drops to one, that is to say, the iron becomes practically non- 
magnetic. 
Or if we take a still more mysterious force, namely gravitation, 
who can fathom its cause? No human being can explain the 
nature of that force which keeps our own planet at the fixed 
distance of ninety-three million miles from the sun, and which 
holds together the whole solar system containing vastly greater 
orbs, and at immeasurably greater distances. 
One of the most remarkable effects of gravitation is seen, when 
approaching the Antarctic regions, in the fall of the barometer, 
which acts precisely as though the ship were sailing up hill. And, 
to a certain extent this is really the case, the vast mountain mass 
of the Antarctic continent drawing the ocean to itself by the force 
of gravitation, so that it resembles an inclined plane, sloping 
upwards to the mass of ice. 
To natural laws, such as these, and to many other branches of 
science, hundreds, I may say thousands, of our ablest men are 
_ devoting their time and abilities, and year by year appliances are 
being perfected whereby observations can be made, which in course 
of time may, and probably will, throw light upon these abstruse " 
points. 
At no time has the art of illustrating every science by photo- 
graph or diagram been so elaborate as during the past year. 
_ Wherever it is possible, the tendengy of our workers is to show the 
_ result of their observations by illustration as mucb as by word. 
In no science is this more apparent than in astronomy. A 
superb photograph of the moon has been presented to the Royal 
Astronomical Society by the Director of the Lick Observatory, 
_ where it was taken by means of the great Lick telescope. The 
details are very sharply defined. During the solar eclipse of 
photograph is more than two feet in diameter, and the lunar » 
