22 



REPOBT< — 1856. 



advantage of another length of cable, giving with the above, an aggregate of 1020 miles. 

 The instruments, one of which was exhibited, seemed to be of great delicacy, capable of 

 the utmost nicety of adjustment and particularly free from sources of error. The 

 records were all made automatically, by electro-chemical decomposition, on chemi- 

 cally prepared paper. The observations of different distances recorded themselves 

 upon the same shp of paper; thus, 0, 83, and 249 miles were imprinted upon one paper, 

 0,83, 498 miles upon another slip, 0, 249, 498 upon another, and 0, 535, 1020 upon 

 another. Thus by the juxtaposition of the several simultaneous records on each 

 slip, as well as by the comparison of one slip with another, the author has been 

 enabled to show most convincingly that the law of the squares is not the law which 

 governs the transmission of signals in submarine circuits. Mr. Whitehouse showed 

 next, by reference to published experiments of Faraday's and Wheatstone's (Philo- 

 sophical Magazine, July, 1855), that the effect of the iron covering with which the 

 cable was surrounded was, electrically speaking, identical with that which would 

 have resulted from submerging the wire, and that the results of the experiments 

 could not on that point be deemed otherwise than reliable. The author next 

 addressed himself to the objections raised against conclusions drawn from experi- 

 ments in "Multiple" cables. Faraday had experimented, he said, upon wires 

 laid in close juxtaposition, and with reliable results ; but an appeal was made to 

 direct experiment, and the amount of induction from wire to wire was weighed, and 

 proved to be as one to ten thousand, and it was found impossible tovaiy the amount 

 of retardation by any variation in the arrangement of the wires. Testimony also 

 on this point was not wanting. The Director of the Black Sea Telegraph, Lieut.- 

 Col. Biddulph, was in England, and present at many of the experiments. He con- 

 firmed our author's view, adding, " that there was quite as much induction and 

 embarrassment of instruments in this cable as he had met with in the Black Sea 

 line." The author considers it therefore proved, " that experiments upon such a 

 cable, fairly and cautiously conducted, may be regarded as real practical tests, and 

 the results obtained as a fair sample of what will ultimately be found to hold good 

 practically in lines laid out in extenso. At the head of each column in the annexed 

 Table is stated the number of observations upon which the result given was com- 

 puted, — every observation being rejected on which there could fall a suspicion of 

 carelessness, inaccuracy, or uncertainty as to the precise conditions ; and, on the 

 other hand, every one which was retained being carefully measured to the hundredth 

 part of a second. This Table is subject to correction, for variation in the state of 

 the battery employed, just as the barometrical observations are subject to correction 

 for temperature. Of this variation as a source of error I am quite aware, but I am 

 not yet in possession of facts enough to supply me with the exact amount of cor- 

 rection required. I prefer, therefore, to let the results stand without correction. 



Amount of Retardation observed at various distances. 

 Time stated in parts of a Second. 



Voltaic Current. 



"Now it needs no long examination of this Table to find that we have the retar- 

 dation following an increasing ratio, that increase being very little beyond the simple 

 arithmetical ratio. I am quite prepared to admit the possibility of an amount of 

 error having crept into these figures, in spite of my precautions ; indeed, I have on 

 that account been anxious to multiply observations in order to obtain most trust- 

 worthy results. But I cannot admit the possibility of error having accumulated to 

 such an extent as to entirely overlay and conceal the operation of the law of the 

 squares, if in reality that law had any bearing on the results. Taking 83 miles as 

 our unit of distance, we have a series of 1, 2, 3, 6, and 12. Taking 166 miles as 

 our unit, we have then a series of 1, 3, and 6. Taking 249 miles, we have still a 

 series of 1, 2, and 4, .in very long distances. Yet even under these circumstances, 

 and with these facilities, I cannot find a trace of the operation of that law." The 



