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New Marvels in Physics
By Ben Winslow
HAT the average Q.-Why do the inhabitants of cold
student knows cor- climates eat fat? How would you find,
A.-An inhabitant of cold climates eats extremely interest- fat principally because he can't get no ing. Probably not lean, also because he wants to raise its
more than one stu- temperature. But if equal weights of dent out of twenty, when he passes sulphur, phosphoorus, and carbon into the preliminary study of physics, burned in his neighborhood, he will give escapes
danger of too little off eating quite so much. The relative knowledge. He gains but smat- quantities of eat given off will depend tering of the subject; learns a few
few upon how much sulphur etc, is burnt and primary principles that are
how near it is burned to him. If I knew strange to him; and straightway falls into these facts, it would be an easy sum to the belief that his knowledge is equal to
find the answer. any occasion. Even before he has fairly entered upon the elementary stages of
Q.-An iceberg floats with one milthe study, he begins to put his new
lion tons of ice above the water line; how knowledge to work. To what extent he many tons are below the water line? can go wrong, is shown by the following
A.—The iceberg floats on top because specimens of examination answers. These
it is lighter, hence no tons are below the answers were taken from fifty or more
water line. Another reason is that an examination papers written by first year students, on acoustics, light, and heat. Of iceberg cannot exceed one million tons
in weight; hence if this much is above course, no one paper contained all the blunders ; and in fact, many of the papers
water, none is below. Ice is exceptional were practically perfect.
to all other bodies except bismuth. All
other bodies have thousand and Q:—What are the conditions favorable ninety feet below the surface and two for the formation of dew?
feet extra for every degree centigrade. If it were not for this, all fish would die,
P. S. When I say one thousand and A.—A body of gas as it ascends, ex
ninety feet, I mean one thousand and pands, cools, and deposits moisture; so if
ninety feet per second. you walk up hill the body of gas inside you expands, gives its heat to you, and Q. How has the velocity of light . deposits its moisture in the form of dew
been measured? or common swet. Hense these are the favorable conditions; moreover, it ex
A.-An atheistic scientist (falsely 50plains why. you get warm by ascending called) tried experiments on the staela hill, in opposition to the well-known lites of Jupiter. He found that he could law of the conservation of energy. delay the eclipse sixteen minutes by
going to the other side of the earths would be a perfect vacuum. The ball orbit; in fact, he found he could make would then bust, but you would not be the eclipse happen when he liked by sim- aware of the fact on account of the loudply shifting his position. Finding that ness of a sound varying with the density credit was given him for determining the of the place in which it was generated, velocity of light, by this means, he re- and not on that on which it is heard. peated it so often that the calendar began to get seriously wrong and there were Q.—Why do water pipes burst in cold riots, and Pope Gregory had to set things weather? right.
A.—People who have not studied Q.—How would you disprove, experi- acoustice think that Thor burst the mentally, the assertion that white light pipes, but we know that it is nothing of passing through a piece of colored glass the kind for Proffessor Tyndall has burst acquires color from the glass? What is the mythologies and has tought us that it that really happens?
it is the natural behavior of water (and
bismuth) without which all fish would A.-To disprove the assertion that die and the earth would be in an iron "white light passing through a piece of grip. glass acquires color from the glass," I would ask the gentleman to observe that Q.-What is the difference between a the glass has just as much color after the "real" and a “virtual” image? Give a light has gone through as it had before. drawing showing the formation of one of That is what really would happen. cach kind.
Q.-A hollow india rubber ball full of A.—You see a real image every mornair is suspended on one arm of a balance ing when you shave. You do not see a and weigled in the air. The whole is virtual image at all. The only people then covered by the receiver of an air- who see virtual images are those who pump. Explain what will happen as the are not quite right. Vertual images are air in the receiver is exhausted.
those things which do not exist. I cannot
give you a reliable drawing of a virtual A.—The ball would expand and en- image, because I never saw one. tirely fill the vessel, driving out all before it. The balance being of greater density It is interesting to analyze these anthan the rest would be the last to go, but swers of blundering students, and enin the end its inertia would be overcome deavor to discover by what mental proand all would be expelled, and there cess they arrived at their conclusions.
On the shores of the lake of the same name, in northern Ontario.
By O. J. Stevenson
NE of the most interesting places
The little town from which the region in America is the Cobalt mining is named, is not yet two years old, and district in northern Ontario yet it contains, besides its transient popinteresting on account of the
ulation, some two or three thousand inwonderful richness of its mineral wealth, habitants, and is, to say the least, unique as well as the peculiarly rapid growth
in its appearance-a city of shacks, huts, of Cobalt and the adjacent mining towns.
and tents mingled in delightful confusion, with here and there a sprinkling of modern houses, theaters, banks, and hotels, to give it an up-to-date appearance, the sign of civilization in the wilderness.
To reach Cobalt, on leaving North Bay, a junction point of the Grand Trunk and Canadian Pacific railroads, on the northern shore of Lake Nipissing, you pass through a hundred miles and more of wilderness, forest, rock, lake, and stream, with nowhere a clearing, and seldom a human habitation. In the fall
of 1904, a Frenchman named La Rose,
Slabs of Silver From TreTheWEY MINE. radius of three or four miles of Cobalt
Slab back of hammer weighs 79 lbs., worth $491. Anal
ysis-66.67 per cent silver, 2.15 cobalt, .41 nickel, lake was taken up, and many new mines
1.60 iron, 7.03 arsenic, 9.67 antimony, .22 sulphur,
6.72 calcium carbonate, 1.23 magnesium carbonate, were discovered. Before the end of the 3.29 insoluble. present season, and less than two years after the first discovery, upwards of fifty And yet this is not so strange after all, mines will be shipping ore from Cobalt. when we consider the peculiar character So far, some three million dollars' worth of the mines. The silver is found only of ore has been shipped.
in narrow veins, generally not more than One of the peculiar things about the three or four inches wide, and showing Cobalt country is that before the final frequently at the surface only a narrow discovery, prospectors had been over and line of silver, perhaps not a quarter of over the ground, had camped time and
an inch wide. Even in the richest mining again on the shores of Cobalt lake, but properties now in operation, some of the had never even suspected the existence best veins have been walked over day of the richest silver mines in America, after day by proprietors and workmen uncounted fortune within their grasp. alike, before being discovered. In the