NATURAL PHILOSOPHY. 127 



the meantime, during the stagnation that has engulfed all such projected 

 schemes since the Atlantic cable was designed and lost, a great reform in 

 the method of constructing submarine ropes has been going steadily forward. 

 The old self-destructive principle of ponderous iron coils for deep-sea wires 

 has been so generally abandoned, that a proposition for now reverting to 

 their use across a sea of any length or depth would not be entertained for a 

 moment by telegraphic engineers. To be sure, this change, which of course 

 was, and still is, fiercely opposed by some of the wire ropcmakers, has not 

 been brought about till the credulity and patience of shareholders were at 

 an end, and until the bottom of the Mediterranean and other seas had been 

 fruitlessly adorned with three or four of those leviathan coils, enduring 

 monuments of our commercial enterprise, and of our mechanical ignorance 

 also. Since that period only four years ago, though marking an age in 

 the infant science of telegraphy opinions have undergone a most impor- 

 tant change, and both contractors and engineers now often lean so strongly 

 to very light cables, that the idea, like all good ideas, is in danger of being 

 led into extremes, and we may see as much public money lost in trying to 

 submerge cobwebs as was ever dragged down "fathoms deep," even by 

 those expensive wire covered cables, big enough and heavy enough to moor 

 an island. The results of this great alteration in the weight and strength of 

 cables are likely soon to be practically tested on the most extensive scale, by 

 the proportionate success or non-success of some cables which are now 

 being manufactured in England. One is about the very lightest cable of its 

 kind that has ever been made at all, always excepting the gutta-percha 

 covered copper wire which was stretched aci'oss'the Black Sea to Balaklava. 

 The other is to be a well proportioned " composite " cable, heavy and 

 very massive, perhaps far too much so in some parts; in others, where it 

 is proposed to be sunk some three miles down, it is, if not quite a light 

 rope, still, with regard to lightness, an important example in the right 

 direction. 



The first mentioned extremely light cable, which will weigh less than 

 three hundredweight per mile in water, is about being constructed at the 

 Electric Cable Company's works, Milwall. The heavier, and we must also 

 say the more expensively proportioned, rope is in progress of manufacture 

 at Glass & Elliot's for the English government, and will, it is hoped, unite 

 England with Gibraltar. In this cable all questions of cost have been con- 

 sidered at the treasury as entirely subordinate to procuring the very best 

 workmanship and material, the highest conditions of mechanical and 

 electrical excellence which it is possible to secure by money, toil, or inge- 

 nuity. The direct route from England to Gibraltar would, for the most part, 

 lie through what in telegraphic works would be called deep water, the 

 route from Brest to Finisterre, and so on round the coast of Portugal, at a 

 comparatively short distance from land, averaging on the whole either one 

 thousand or more than one thousand fathoms. But in this cable (as should 

 have been the case with every one that has ever been made) the contract 

 with Glass & Elliot is not only for its manufacture on a certain plan, but for 

 submerging it successfully. The depth of water in which it will ultimately 

 be laid will therefore, doubtless, rest in a gi-eat measure with the contractors; 

 subject, of course, to certain conditions of the government, that it shall be 

 sunk in water deep enough to keep it out of the reach of any enemy, either 

 to raise or to break. The latter consideration is, of course, one of the last 

 importance; since only in war time will attempts be made to injure it, and 



