Act lv; Fig- 46 tobel of the Glock in Fig. 45; note lhot reference is mode lo winding weighls

Transcription

1 Act lv; Fig- 46 tobel of the Glock in Fig. 45; note lhot reference is mode lo winding weighls

2 Act lv; Fig. 47 long pendulurn 3O-hout sleeple Glock, stondqrd ogee movemenl powered by o spring-tusee unit. Insteod of chonging the escope wheel to qllow _for q,hort pendulum, Jerome hung o long pendulum froin ihe peok of lhe aos

3 Acl lv; Fig. 48 Here ogoin the long pendulum is ernployed lqs in Fig. 4Z) in this 3O-hour colloge limepiece

4 Acf:lvt Fig doy steeple clock with wirc restrqints lg keep the iprings from soeging; note the <enler pillor to which both springs ore qfloched

5 Act V: Balance-uTheel Clocks mentation and produciion. These then sorted themselves out and by the Iatter 1850's' the balance wheel or marine clock that we see fot many years thereaftet had evolved and become dominant. It is interesting to see that one of the first actors on stage in this set is the same Charles Kirk who was prominent in Act II. This time, however, even though his early contributions are most interesting from the horological point of view, they seem to have had little lasting impact.as His patent of l81r75o covers a clock wifh two very curious features. First, it has a peculiar escapement that sports a double escape wheel. Second, it has time and strike running from a common spring. This clock was produced by the Marine Clock Manufacturing Co., New Haven, Connecticut (Figure >0).51 The Kirk marine clock, originally with only a 30-hour duration, was also produced as an 8-day timepiece in two variations. The first and most commonly seen has the spring mounted separately from the movement (Figures t1 and t2). The spring is contained in a casr iron barrel which is connected by a chain to a fusee in the movement proper. This model appears both as time only and time with sttike. The striking version has a second spring without fusee. AIthough the fusee in the time kain shares the a$or with the great wheel, it has thc incorrect shape of the reverse fusee.s2 The second and Iess commonly seen var.iant has the -spring mounted within the movcment (Figure 53). Here, too, the spring is in an iron containment and there is a fusee of the wrong shape.b3 The earliest patent covering a balance-wheel clock is one issued to Eli Terry in The fruits of this patent are seen in a large steeple clock that appears with the label of his son, Silas B. Terry (F.igure 54). S. B. Terry's connection with the early spring-clock business was considerable. He is credited with a process for the tempering of steel springs, a ptocess that he allowed Dunbar, the Bristol spring manufacturer, to use.66 The movement of this large steeple, although associated with his uncle's patent, is remarkably similar to the movement of a weight-driven balance-wheel clockse he had made. Finally, he can be credited with several more novel clocks belonging to this whole general period. In the early 1850's S. B. Terry produced some very small balance-wheel clocks thai appeared in a varicty of cases. Shown here is the distinctive candlestand clock with this movement (Figure 55). In 1852 he patented thc now famous torsion pcndulum clock, in which a dumbbell-shaped balance oscillates on a flat wire. These were always of 30-hour duration ind nearly always appeared as timepieces only, although occasionally they incorporated a strike train (Fig,.rre 561.sz During these few years around 1810 when the balance-wheel clock was struggling for its identity, several novel escapements came and went. $7e have already seen one of these in the Kirk clocks with the double-escape wheel. Another is found in the papier-mache clocks made by the Litchfield Manufacturing Co.58 The escapements used resemble the Sully or Enderlin escapements familiar to the vratch collectors. These docks are found in both 8.day and 30-hour variants (Figures 57,58 and 59).

6 There is a distinctive glass dome as if the ma escadement of this clock escjdement.bs The clock is nianufachrred by Jerome.Go In Act III we saw t}re fusee timepiece classified as Type 4C and attributed tentatively to Noah Pomeroy. The iariation in detail arning examples of this movement suggests that this type never really left the experimental phase. Now we see a veriilon of the same'movement that carries a -balance wfreel coupled with a chronometer escap ment ( Figure 61). This example is found in a case with an A&ins label. The last four clocks of this act are used to illustrate balance-wheel movements that are closer in design to those found in the following the Civil rtrzar. First we exarnine an 8-day dou made bv Elisha Manross (Figure 62). This rnovernent is 9", a rcf' erence to a patent granted to Levi Beach.61 The case is a large reverse ogee mirror tlrat is obviously intended to serve as a Piece of furniture as well as repository for the clock. Next is a 3O-hour octagon marine clock by E. N. \Zelch (Figure 63) ' This clock, and its 8-day counterpat, would date to about 1855' Finallv we have a pair of Terome balance-wheel clocks in similar cases with iron froits of onosoi design- (Figures 64 65). They are both of 30-hour duration; one is a timepiece only while the ^nd other includes a strike train. 64