3 



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. Hopkiuson, in his recent interesting address 

 before the Society of Electrical Engineers, " The more we know of 

 magnetism the more remarkable does it appear. We kuovv 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 m 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 if 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, hun'lreds, I may say thousands, of our ablest men are 

 devotmg 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 lime 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 tendency 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 Eoyal 

 Astronomical Society by the Director of the Lick Observatory, 

 where it was taken by means of the great Lick telescope. The 

 photograph is more than two feet in diameter, and the lunar 

 details are very sharply defined. During the solar eclipse of 



