40 ANNUAL OF SCIENTIFIC DISCOVERY. 



We may observe, in conclusion, that there is no fear of the 

 rubber parting from the plates to which it is attached by Sterne's 

 process. Its adhesion has been tested by Mr. Kirkaldy, who 

 found that a direct pull of 6,216 pounds, or 177| pounds per 

 square inch, was required to separate the two. In compression 

 the rubber segments stood 66| tons per square foot, returning to 

 their normal condition after the pressure was removed. 



THE USE OF WIRE ROPE IN CIVIL AND MECHANICAL ENGI- 

 NEERING. 



A marked feature of present mechanical progress is the in- 

 creasing use of wire rope in civil and mechanical engineering. 

 The world probably owes a greater debt to the late John A. 

 Roebling than to any other man connected with the introduction 

 of wire cables as a constructive material. It was he who, by his 

 scientific employment of this material, educated the public at 

 least the American public up to the full appreciation of its 

 value. From his labors and experiments the principal data upon 

 which other engineers now depend in the use of wire for con- 

 structive purposes have been chiefly obtained. 



Now we find wire rope employed in almost every engineering 

 work. It constitutes an important part of modern ship-rigging. 

 It is used for hoisting, for towing boats, for bridges, for sus- 

 pended tramways, for propulsion of cars up heavy grades, and 

 even upon level surfaces. It is found to be the cheapest and most 

 efficient medium for the transmission of power to long distances. 

 Every year increases the number and extent of its applications. 



Two of the most recent applications to which this material has 

 been put are, in our opinion, destined to prove equal in impor- 

 tance to any which have preceded them. We allude to the trans- 

 mission of motive power, and the tramway system invented by 

 Mr. Hodgson, of which several notices have recently appeared in 

 these columns. 



The telo-dynamic cable system is, if we mistake not, destined 

 to a most brilliant future. This country affords a notable field for 

 its advantageous employment. Our mining districts are, many 

 of them, so situated that power can only be obtained in this man- 

 ner, or by the use of steam. 



We do not entertain a doubt either that the wire-rope tramway 

 system will be found of vast benefit to our mineral districts. It 

 is simple, practical, and cheap, and has demonstrated its value as 

 a means of transporting ores and freights. 



To what other uses wire rope may be destined it is impossible 

 at present to say, but the success which has attended its applica- 

 tions thus far encourages the belief that inventors and engineers 

 may still find it a valuable resource for purposes not yet thought 

 of, and in ways hitherto undiscovered. Scientific American. 



THE WIRE-ROPE TRAMWAY AT BRIGHTON, ENGLAND. 



The wire-rope transport system may be described as consisting 

 of an endless wire rope running over a series of pulleys earned 



