Figure i . — Breguet's Tourbillon. At C) is sliown the carriage which revolves with pinion B carrying iho escape- 

 ment and balance around the stationary wheel G. (After G. A. Baillie, Watches, their history, decoration, and 



mechanism, London, Methuen, n.d.) 



minute, so that with each revolution all possible posi- 

 tions were passed throus;h (fisj. 1). This gave the 

 watch an average rate which was constant except for 

 variations within the period of revolution of the 

 chariot. Only a very skillful workman could, however, 

 work with the delicacy necessary to produce such a 

 mechanism. The result was that few were made and 

 these were so expensive that it continued to be 

 more practical to poise the parts in a conxentional 

 mo\ement. The idea of revolving the entire train cf 

 a watch, including the escapement, seems to have 

 evolved surprisingly slowly from Breguet's basic 

 invention cf the revolving escapement. In construct- 

 ing a watch wherein the entire train revolves, no such 

 delicate or precise workmanship is required as in the 

 tourbillon. Due to the longer train of gears involved 

 the period of re\olution is much slower. Position 

 errors average out as certainly if not as frequently. 

 In Bonniksen's "Karrusel" watch of 1893 - the dura- 

 tion of a cycle is 52.5 minutes' while in the Auburn- 

 dale Rotary which we are about to discuss the period 

 of each revolution is IH hours. 



The Invention 



The patent model of Jason R. Hopkins" revolving 

 watch, now in the U. S. National Museum,* was not 

 the first in which the entire train revolved but it was 

 a very no\el conception intended to reduce greatly 



- British patent 21421, srrantrd January 21, 1893. 

 3 Chamberlain, op. cit. (footnote 1 I, pp. 229, 230. 

 'Cat. no. 309025; U. S. patent 161513, July 20, 1875. 



PAPER 4: AUBURNDALE WATCH COMPANY 



the number of parts usually associated with any 

 watch. This may be seen froin figures 2 and 3, where 

 everything shown inside the ring gear revolves slowly 

 as the main spring runs down. This spring is pre- 

 vented from running down at its own speed by the 

 train pinion seen in mesh with the ring gear. Through 

 this pinion motion is imparted to the escape wheel and 

 balance, where the rate of the watch is controlled. 

 The balance, being planted at the center of revolu- 

 tion, travels around its own axis, as in the tourbillon, 

 at the speed with which the entire train revolves 

 around the barrel arbor. This arbor turns only 

 during winding. No dial or dial gearing is shown in 

 the patent or exists in the patent model. The patent 

 merely says, casually, "By means cf dial wheels the 

 motion of the barrel may be communicated to hands 

 and the time indicated in the usual manner." No 

 fine finish or jeweling has been lavished on the 

 model, the only jewels present being in the balance 

 cock which was utilized as it came from its original 

 watch with only minor modification to the shape of 

 its foot. Apparently the balance wheel itself is also 

 a relic of the same or a similar conventional watch. 

 There is no jeweling in the escapement or on the 

 other end of the balance staff. In spite of this the 

 model runs very actively and will overbank if wound up 

 very far. The beat of the escapement is two per 

 second and the movement revolves once in 20 minutes. 

 There are two great faults in the model. First is 

 the lack of an adequate bearing for the barrel to 

 turn on. There is only one very short bearing a long 

 way removed from the point of engagement between 



51 



