108 GOODYEAR ON GUM-ELASTIC. 



been carried in so short a period is remarkable. As near as can 

 be ascertained, there has been an average of one thousand 

 pounds of gum per day manufactured into this kind of car springs, 

 during the year 1849. 



A subsequent improvement has been made in car springs by 

 Mr. Ray, by making the spring of one block of gum, and hooping 

 it with iron rings, instead of using alternate discs of India rubber 

 and metal. 



These springs act by the elasticity of the gum by compres- 

 sion. It is applied in the manner represented in plate xvii., 

 fig. 2. To speak of the importance of an article so generally 

 used upon railroads, is needless. 



A diagram is given, fig. 3, of a car spring, which, it is thought, 

 may be an improvement in the construction of car springs, on 

 account of the greater lateral motion obtained by it.* Several 

 kinds of air springs have also been invented by different in- 

 dividuals, made of vulcanized gum-elastic, one of which is rep- 

 resented by figs. 4 and 5, plate xvii. ;f another, which is repre- 

 sented by figs. 6 and 7. J 



CARRIAGE AND COACH SPRINGS. 



There is more difficulty in applying this substance to coaches 

 and carriages for common roads, so as to preserve a good ap- 

 pearance of the vehicle, on account of the lateral motion that is 

 necessary to be had, than there is in applying it to cars. They 

 have been applied very successfully, so as to ease off the strain 

 from elliptic springs, which may be made light and weak for the 

 purpose, when arranged in the manner represented in the dia- 

 gram, plate xvii., fig. 8. 



* Invented by Mr. E. M. Chaffee, of New Haven, 

 t Invented by Mr. John Lewis, of New Haven. 

 t Invented by Mr. of New Haven. 



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