Febeitaey 23, 1883. 



SCIENCE. 



65 



as in a Latin version. Bj' means of these pho- 

 tographic copies of the map, the legends in 

 Spanish are made accessible. I am not awai'e 

 that thej' ha\'e ever been published as a whole. 

 There is something anore than a suspicion that 

 some of the legends in Latin contain state- 

 ments not to be found in the Spanish. A com- 

 mittee of the Massachusetts historical society, 

 to whom a cop_y of this map, presented bj- the 

 president, has been referred, intend to publish 

 an English translation of the legends, with the 

 result of a comparison with the Latin version. 

 Charles Deane. 



MAP OF THE PLANETS AND STARS 

 NEAR THE SUN, MAY 6, 188S. . 



The map vrhich is given in this number of 

 Science has been prepared to aid astronomers, 

 who may observe the total solar eclipse of this 

 year, in a search for Vulcan. It does not 

 need to be said that the eclipse of May 6 is 

 the most favorable for this purpose that will 

 occur for many j'ears, and it is to be hoped 

 that the unique opportunity will not be lost. 



The present map has been compiled with 

 care from the Dwrchmusterung catalogue, 

 checked by comparison with the maps and by 

 proof-reading. It contains all the stars of the 

 Durchmusterung within the region near the 

 sun, down to the seventh magnitude inclusive, 

 together with a few stars of a slightly lower 

 magnitude, which are only added when their 

 omission would spoil a configuration. The 

 planets Saturn and Neptune are also added. 

 The positions of the map are amply accurate 

 for the purpose intended. 



Edward S. Holden. 



FIRST USE OF WIRE IN DEEP-SEA 

 SOUNDING. 



In view of the great impetus recently given 

 to deep-sea sounding and dredging (especially 

 in the United-States navj' and coast survey 

 work) by the application of steel piano-wire 

 in place of line, it is interestiug to learn the 

 fate of the first experiments in that direction. 

 These have been extracted bj' Commander 

 J. R. Bartlett, U.S.N., of the hydrographic 

 office, from the log-book of the United-States 

 schooner Tane}', Lieut. J. Walsh, U.S.N., 

 commanding, October, 1849, to June, 1850. 



The Taney took on board at the Brooklyn 

 navy-yard, Oct. 22, 1849, a large iron reel 

 containing 7,000 fathoms iron wire graduated 

 Nos. 7 to 13 ; an extra reel with 5,900 fathoms 



wire, size not stated ; and a small reel with 300 

 fathoms iron wire, size No. 5. 



The Taney sailed Oct. 26, 1849, to take deep- 

 sea soundings in the North Atlantic. On 

 the 15th of November preparations were made 

 for sounding with wire in lat. 31° 59' N., long. 

 58° 43'. 5 W., not far from Bermuda. After 

 reeling out 5,700 fathoms, the wire parted 

 near the surface, owing to the fact that 

 the splices had some projecting ends which 

 caught upon each other. The No. 7 wire 

 parted. It is noted in the log, that the cir- 

 cumstances were favorable and the sounding 

 plumb. It seems, however, that the lead used 

 was altogether too small, about twelve pounds 

 onlj' ; and this was the reason wh}' so much 

 wire ran out without its being recognized that 

 bottom had been reached. The weight of the 

 wire of course carried it out, and would have 

 continued to do so as long as any wire was 

 left. The lead was armed with a Stellwagen 

 cup, but the detaching apparatus and dj^na- 

 mometer for sounding were then unknown. 



The same experience was repeated on the 

 9th of May, 1850, when 2,200 fathoms of wire 

 were lost ; and on the 18th, when 2,050 fatlioms 

 were lost, with the thermometer, twelve-pound 

 lead, and Stellwagen cup.' On the 22d of 

 Maj^ the last attempt was made with the same 

 results ; the wire parting in every instance 

 owing to one splice catching upon another on 

 or near the reel. The last time onlj- an eight- 

 pound lead was used, with 1,900 fathoms of 

 wire out when it parted. The partj' returned 

 to New York, June 3, 1850, shortly after which 

 Lieut. Walsh died. This ended the trial of 

 wire for the time ; to be revived when the in- 

 vention of steam reeling-apparatus, detacliing 

 sounding-cups, the dynamometer, and ' accu- 

 mulators ' had rendered its use practicable. 

 It seems singular, however, that the difficulty 

 as to the splices was not remedied on the 

 spot, and that heavj' leads were not tried. 



William H. Dall. 



AN EXTENSION OF THE THEOREM OF 

 THE VI RIAL AND ITS APPLICATION 

 TO THE KINETIC THEORY OF THE 

 CONSTITUTION OF GASES.^ 



Clausius has designated as the theorem of the 

 virial the equation wliicli he first arrived at in a 

 paper upon a New mechanical theorem ap2)Ucable to 

 heal.- Tliis tlieorem applies to stationary progressive 

 motion, sucli as tlie molecules of gases are assumed 

 to have in the kinetic theory of gases, and, when so 

 applied, may be written in tlie form 



akt- i-pv + i^rR . . . . (1) 



1 Abstract of a paper read by H. T. Eddy, Ph.D., Univer- 

 sity of Cincinnati, before tbe Otiio raecbanics' institute, Jan. 18, 

 1883. 2 Phil. jnag. [4] , vol. 40, p. 122 . 



