268 



SCIENCE. 



[N. S. VoL.XXIII. No. 581. 



Carolina in coastal plain deposits; and those 

 of Indiana in sandstone. 



Continuously sucking wells are reported in 

 Georgia and Nebraska, but in general the 

 wells are of the breathing type, the movement 

 being outward or inwa^rd according to baromet- 

 ric pressure. 



Symbols for Representing Underground Water 

 Data: Discvission by members of the so- 

 ciety. 



To secure uniformity it is considered ad- 

 visable to adopt some simple set of symbols 

 for use in reports. A circle for wells and a 

 circle with a short irregular line leading off 

 from it (suggesting a stream) for springs were 

 favored. For successful wells the circle is to 

 be made solid (dot), while for unsuccessful 

 wells the circle alone is to be used. Mineral 

 wells are indicated by a dot within the circle. 

 A vertical bar for waters which rise in the 

 wells, a cross (consisting of vertical and hori- 

 zontal lines) for flows, and a horizontal bar 

 for thermal properties in springs were sug- 

 gested, each to be superimposed on the fixed 

 symbol for common or mineral wells and 

 springs. M. L. Fuller, 



Secretary. 



DISCUSSION AWD CORRESPONDENCE. 



A NEW WOELD FOR THE BLIND. 



In Harper's Magazine for January, 1860, 

 there is a story by J. D. Whelpley called, 

 ' The Atoms of Chladni.' The tale itself has 

 interest for the curious only, but it pivots 

 upon a contrivance which, as described, is an 

 illustration of the fact that the fancy of man 

 has often anticipated the scientific discoveries 

 of a succeeding time. ' The old discoveries of 

 Chladni ' are alluded to as the initial idea 

 whence sprang the mechanism devised by 

 'Bonsall,' the Merlin and Mephisto of the 

 tale. A broad plate of thin metal is described 

 as suspended from the ceiling by threads of 

 silk. This plate may be ' electrified by vibra- 

 tion.' 



Tlie mirrors of your ceiling are each a vibrating 

 plate. From the upper surface of these rise 

 wire conductors of tlie electric power generated 

 by the vibration. This is faint and feeble at 



first, but, by passing through metallic threads 

 coiled a thousand times around small magnets 

 each geometric division of the plate corresponding 

 with a magnet and with a radical sovuid of the 

 human voice — it- has power to connect and dis- 

 connect the keys of the batteries. » * * Thus 

 are pinned more or fewer points in this strip, of 

 paper, from which, by such wonderful means, has 

 been read off and written every clearly articulated 

 sound uttered in your apartments. There are 

 ninety distinct entries of tlie record, said Bonsall, 

 closing the book, and -of these more than twenty 

 are conversations between the same pair of affec- 

 tionate lovers. All must have taken place in 

 your room. Your villainous machine records 

 words spoken in your room, above the mirror, as 

 clearly as if they had been uttered below it, in 

 ray chamber. 



Within the past year or two there have 

 appeared in the magazines and newspapers of 

 the world accounts of a remarkable invention. 

 From one of these — The Boston Evening 

 Transcript, October 14, 1905 — I quote the fol- 

 lowing account : 



Conceive a piece of steel wire, generally known 

 as ■ piano wire,' stretched between two points, or 

 a steel plate. Take an ordinary electromagnet 

 and connect the coil of it in circuit with the sec- 

 ondary of an induction coil, the primary of which 

 is in circuit with a microphone and battery. On 

 speaking into the microphone induced currents 

 of electricity produce continuous variations in the 

 Held strength of the electromagnet, and if we 

 slide the electromagnet along the steel wire or 

 over the plate the magnetic fluctuations of the 

 electromagnet affect the steel wire or plate in 

 the form of variable magnet intensities. There 

 have been impressed on the steel surface undula- 

 tions of magnetization, a kind of writing that is 

 virtually permanent, and which faithfully records 

 the articulations of the voice. If the coils of 

 the electromagnet ai'e connected with the tele- 

 phone receiver, and the magnet is made to travel 

 over the steel wire again, the telephone receiver 

 repeats what was spoken into the microphone; 

 or, in other Avords, acoustic vibrations analogous 

 to the original vibrations of the microphone are 

 produced in the telephone receiver. The records 

 thus made will last for years. The steel wire 

 or plate may be polished without disturbing it. 

 Rust has no effect upon the record. The message 

 remains there until a heavier magnet is drawn 

 over the wire, when it is wiped off or demagnetized. 



In one form of the machine a steel plate is 



