496 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



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Immor, and tlie cataract might result from too iarg-e a percentage of albu- 

 men in that secretion. The cure might be effected, first by injecting water 

 into the aqueous huinor, or, second, by tapping the, aqueous cjiaiuber in 

 the hope that the new secretion would contain less albumen than the old. 

 The cure of the soft cataract, on the other hand, would be effected by intro- 

 ducing albumen into the aqueous humour. These views have since re- 

 ceived confirmation from various researches of physiologists. 



Metamorphoses in Fishes. 



Prof. Agassiz, of Harvard College, in a communication to the Paris 

 Academy of- Sciences, states that he has lately observed certain fishes un- 

 dergo metamorphoses quite as marked as that of the tadpole to the frog, 

 and he expresses the opinion that a natural classification of fishes can be 

 founded on the correspondence which exists between the embryonic de- 

 velopments and the complication of their structure in the developed state. 



Iron and Steel Shavings. 



The long spirals resulting from turning iron or steel in a lathe have been 

 found by M. Greiss to possess very decided and permanent magnetic pi'op- 

 erties. This is particularly the case with shavings from soft iron. The 

 pnd of the turning first made is found to be invariably the south pole, and 

 the last end made the north pole. Mr. Greiss also observed that the shav- 

 ing whose revolutions were made in an opposite direction to those of the 

 hands of a watch, the observer being the south pole, were more magnetic 

 than those corresponding with the motions of the watch hands. 



Elasticity of Steel Wires. 



Prof. J. C. Maxwell thus writes to Dr. Tyndall, of the Royal Institution, 

 London: I have been swinging discs, &c., by torsion a good deal, and I , 

 find that after a steel wire has been twisted until it takes a slight set, and 

 so has a new position of equilibrium, it gradually entwists itself with a 

 ver}' slow motion, so that after four hours it is still creeping back to its 

 position before it was twisted. A wire twisted and allowed to untwist 

 back to its first position, undergoing a slow molecular change, is therefore 

 not only a reservoir of energy, like the wound up spring of a watch at rest, 

 but a moving agent like a watch going, because it gradually uncoils itself. 

 I suppose the strained state of the external parts is gradually overcome 

 by the constant torsion force arising from the inner parts of the wire, which 

 are never overstrained. I find that the set produced by very slight torsion 

 is as the -square of the angle of torsion; just as in the case of very slight 

 magnetization the resident magnetism is as the square of the maximum. 



Manufacturing and Use of Bells. 



This being the subject for the evening, Mr. Watson made some diagrams 

 on the black-board, illustrating tiie meth<;d of making the moulds for cast- 

 ing large bells. Ho said, it was remarkable that the largest casting we 

 have, was made by people that we look upon as semi-barbarians. The 

 great bell of Moscow, which was cast a little before the year 1600 and 

 weighing 400,000 pounds, excites our admiration. The mere money value 



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