.S7A' WILLIAM SIEMENS, l-.R.S. \ \ j 



to allow of a slight amount of yielding in the hydraulic brake, and 

 to give it a sort of elastic action, the four-way cock I was itself 

 made with a small hole through the plug, as shown to a larger 

 scale in Fig. 8, through which a constant small leakage took 

 place from the pressure side into the exhaust pipe. The brake R 

 was rendered self-relieving by the lever T, Fig. 6, in the same 

 manner as described in the paper. There were two of the friction 

 brakes R R, Fig. 2, one on each side of the paying-out drum B ; 

 and the two rising pipes N N from the brake cylinders K K both 

 fiik'ivd under the same regulating valve J, Fig. 7, whereby the 

 load was maintained always exactly equal upon both brakes. The 

 water escaping from under the valve J into the tank P was 

 delivered by a pipe U upon the top of each of the brakes for the 

 purpose of lubricating them. When driving the drum B in the 

 contrary direction, for picking up the cable, it was only necessary 

 to reverse the four- way cock I ; and the pressure then acting 

 below the piston in the hydraulic cylinder K slacked the brake 

 strap off the brake, while at the same time the lubrication by the 

 waste water from the tank P continued undiminished, so that the 

 drum B revolved freely without the action of the brakes. 



In the laying of the Atlantic cable he was glad to see that water- 

 tight tanks had been adopted for containing the cable on board 

 the Great Eastern, as that was a measure which he had recom- 

 mended for many years, because it preserved the cable from 

 injury and allowed of a system of continuous tests during the 

 whole time of the laying. In addition to the water-tight tank 

 containing the cable in flakes or layers, an arrangement employed 

 for light cables in the Dix Decembre was to carry the coil of cable 

 upon a circular turntable revolving on a set of live rollers in the 

 water tank, as shown in Fig. 3. 



With regard to the grappling for the recovery of the cable of 

 18G5, one fortunate circumstance connected with the Atlantic 

 Ocean was that its bottom appeared to be perfectly smooth and 

 homogeneous. In the Mediterranean sea, however, where he had 

 grappled a cable at a depth nearly but not quite equal to that of 

 the Atlantic, the circumstances had been much less favourable in 

 those respects ; and the dynamometer was therefore by no means 

 so steady, but was liable to fly up suddenly to perhaps 1 5 cwts. 

 and drop down again to 4 or 5 cwts., so that it was impossible to 



