i 7 8 



HA RD WICKE'S SCIENCE- G OS SIP. 



Acres and acres are to be seen covered with the fish 

 thus drying. 



From what I could learn from the French fishermen, 

 they dry their fish on board, and what I saw of the 

 ships by no means excited admiration of their clean- 

 liness. If a fungus of any kind should be started 

 among fish thus cured and thus stored, it would 

 spread rapidly, the ship would be stocked with spores 

 ready to propagate on the arrival of each cargo. The 

 Norwegian fish after drying are stacked in the open 

 air at the fishing-station ; then in like manner on the 

 "yechts" that carry them to Bergen, then in the wharfs 

 at Bergen, from which port they are shipped to their 

 final destination — Spain, Portugal, and Mediterranean 

 Catholic countries, where they are purchased for 

 consumption on fastfdays. These stacks appear from 

 a short distance like hay or corn ricks. 



The Fluidity of Metals. — Prof. W. Spring, of 

 Liege, has for some time past been engaged in a very 

 interesting series of experiments which prove that 

 metals are not solid, and throw considerable doubt 

 on the solidity of everything. Fluidity is simply the 

 property of yielding to pressure in such a manner 

 that the matter in question shapes itself in accordance 

 with the pressure, by the movement of itself upon 

 itself. When water "finds its level," it is simply 

 yielding thus to the pressure of its own gravitation. 

 When it fills a cup or other vessel it is shaping itself 

 as above described, and thereby attaining equilibrium. 



Spring's experiments show that metals, in what we 

 call the solid state, flow in like manner, provided 

 the pressure is sufficiently great. By mixing copper- 

 filings with zinc-filings, and submitting them to a 

 very great pressure, he obtained a lump, and this 

 lump was not a conglomeration of zinc and copper 

 particles, but a true alloy, a piece of brass such as he 

 would have obtained had he fused the materials 

 together in a crucible. Bismuth melts at 51 2°, cad- 

 mium at 442 , and tin at 45 1° ; the mean of these is 

 468 ; but if these metals be melted together in the 

 proportions for making " Wood's alloy," we obtain a 

 silver-like metallic substance that fuses at 113 , or 

 99 below the boiling-point of water. By mixing 

 filings, of these metals together in the same propor- 

 tions, and submitting them to a pressure of 7500 

 atmospheres, M. Spring obtained this alloy, with its 

 low melting-point. By squeezing together in like 

 manner a mixture of powdered sulphur and metal 

 filings, he obtained true sulphides of the metals, i.e. 

 compounds which had lost the properties of both the 

 sulphur and of the metals, and had acquired new and 

 special properties peculiar to themselves. 



In the course of a recent lecture at the Royal Insti- 

 tution on " Certain Properties Common to Fluids and 

 Solid Metals," Professor Chandler Roberts Austen de- 

 scribed these experiments, but he does not appear to 

 understand the cosmical bearings of the results, which 

 I pointed out in the " Gentleman's Magazine" of Feb. 



1883, viz. that they settle the much-disputed ques- 

 tion of the fluidity or solidity of the interior of the 

 earth and other similar planets. The pressure of 

 2000 to 7500 atmospheres used in Spring's experi- 

 ments is attained at only a moderate depth below the 

 earth's surface — moderate, I mean, in comparison to 

 the earth's diameter. As these and vastly greater 

 pressures are reached, the fluidity of the materials of 

 the earth must be attained, whatever be their tem- 

 perature. If this is high, as our borings and sinkings 

 suggest, the pressure demanded to produce interflow 

 is proportionally less. Spring found, that at 2000 

 atmospheres pressure lead-filings became united to 

 an uniform block, and at 5000 atmospheres "it 

 oozed out at all the points of the apparatus as if it 

 were liquid." 



In round figures this pressure of 5000 atmospheres 

 is reached at 50,000 feet below the earth's surface, or 

 more than double this pressure at 100,000 feet, and 

 100,000 feet is not quite 19 miles, or less than -^ of 

 the earth's diameter. This would be represented on 

 a twelve-inch globe by a thickness of -j— of an inch, 

 or that of a stout card. What must be the pressure, 

 and how complete the fluidity, when we descend 

 to a depth comparable to the relative thickness of 

 the rind of an orange ? Is it at all surprising that 

 lava, i.e. fluid rock, should squeeze out of the joints 

 of the earth's crust, as the lead from the joints of 

 Spring's apparatus ? 



The Planet Neith. — Seven times has a tele- 

 scopic body been observed near Venus in such a 

 position as to suggest that it is a satellite to that 

 planet. Mr. J. C. Houzeau, of the Brussels Obser- 

 vatory, has collated these observations, and finds 

 that they do not accord with the satellite theory, 

 neither do they agree with the supposition of an 

 intra-Mercurial planet. He finds that they may be 

 explained, by supposing the existence of a small 

 planet that travels in an orbit about equal to, or a 

 little larger than that of Venus, and that it comes 

 in conjunction with Venus at intervals which are 

 multiples of a little less than three years ; those 

 between the seven observations corresponding to 

 such a period. M. Houzeau proposes the name of 

 Neith for this hypothetical planet. 



Over Drainage. — Mr. M. C. Read has lately 

 read at the United States Department of Agriculture 

 a series of papers on "The Proper Value and 

 Management of Government Timber-Lands," in one 

 of which, read in May last, he shows that more 

 harm than good has been done by the vigorous pro- 

 ceedings of the last twenty-five years in the draining of 

 swamps. These being generally on high ground and 

 at the same level as the surface of adjoining lakes, the 

 drainage is easily effected by deepening the outlets 

 of the lakes, and, when necessary, also straightening 

 and clearing the streams below, which carry off the 



