METAL TIE NOTES. 



The following matter lias been appended as of interest in the discus- 

 sion ol* the desirable change from wooden to metal ties. 



These notes originate in x^art with Mr. Tratman, or else are copied 

 from other publications. 



The ephemeral literature on the subject is growing rapidly, and by 

 the time Mr. Tratman's final report will go to press, it will have become 

 desirable, wath it, to present in abstract the useful information which 

 has thus accumulated. B^^ that time it is hoped that more experiences 

 from trial tests on railroad lines of our own country may also be re- 

 corded. 



As this Bulletin goes to press, two interesting items of news on the 

 railroad tie question have reached this ofSce. The one relates to the 

 remarkable durability of lignum- vitse cross- ties on the Panama Eail- 

 road — thirty-five years. That there is any likelihood, as some papers 

 seem to anticipate, that this discovery will in any way influence the 

 use of metal ties by possible competition of this wooden tie, I am in- 

 clined, for various reasons, to doubt. 



Perhaps of more influence on this subject may become the introduc- 

 tion of stone sleepers in combination with the ^'Elastic Tie-Plate," 

 which was originally intended to improve the track on wooden ties, but 

 has proved itself of service on rock sleepers in an experiment made by 

 the Ystad-Eslof Eailway in Sweden. Yet we are inclined to think that 

 even this kind of substructure, if found as efficient as is claimed, would 

 not threaten as much competition with the metal track as it might at* 

 first appear to do, except under special conditions. 



The theoretical requisites for a perfect metal tie are now quite well 

 understood and have been discussed at length in Bulletin I, from this 

 Division. The task of inventors henceforth must be, while complying 

 with these theoretical requisites, to do it in such a manner as to reduce 

 the cost of the manufacture to its lowest possible figure without loss of 

 required strength. With the extendeg experience before us there can 

 not longer be a doubt that it is possible to construct a metal tie which will 

 be superior in all respects to wooden ties; yet to bring its first cost down 

 to such a figure that the future saving in its maintenance need not en- 

 ter into consideration, but may be taken as au agreeable surprise in 



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