CLOCK-MANUFACTURE IN TI1E UNITED STATES. American clocks were first manufactured in Con necticut, about 1800, by Eli Terry. His clocks soon became popular, and he continued in busi ness until his death, when his sons succeeded him, under the name of the 'Terry Manufac turing Company.' Many neighboring establish ments were soon engaged in clock-manufacture, and Connecticut is still the centre of the indus try in the United States. .According to the census of 1850, there were 1436 clock-factories and 2901 watch-factories in the United States. At first the movements were constructed of wood, and in the better clocks the pendulum was of wood overlaid with gold-leaf. In 1814 Terry invented the 'short-shelf clock,' which rapidly displaced the long or hanging clocks previously made. Brass-wheel clocks were not made in the United States until IS37. American manu facturers introduced the system of cutting out the parts from sheet brass with a die, instead of casting them—a method which at once in sured greater accuracy as well as cheapness in the product. The adoption of the die and of other forms of automatic machinery in the manu facture of clocks has now been carried to such an extent that nothing is left for the skilled lia»d-laborer but the collocation of the parts. Coiled springs, instead of pendulums, had been used in European clocks for two hunched years before their use was introduced into American factories; but they were placed only ill the most expensive clocks: the invention of a reliable but cheap steel spring, which could be placed in the least expensive is due to American enter prise, and its introduction has revolutionized the clock-making industry. The small spring clocks
can be manufactured and sold for less than one dollar, and are very popular.
IlIBLIOGRAMIY. The following are general works on horology: Saullier, Treatise on Modcra Horology in Theory and trans. from the French. by .Julien Tuppier and Edward Rigg (London, 1897) ; Kendall, History of hutch's and Other Timekeepers ( London, 1897) ; Grin thorge, Rudimentary Treatise on. Clocks, Watches, and. Bells (L•udolt, 18S3). In the Journal of the Society of _Iris (London) for March 7, 1890, is an interesting article by Julien Tuplin, ou "Recent Progress in Braid]. Watch and Clock The Supplement of the Ncientific American for September 19, contains an article translated from the French on "Clocks Provided with Automatons." The Philadelphia City-Hall Clock is described ill the Journal of the Franklin Institute (Phila delphia) for February, 1901. The Electrician (London) for December 22, 1899, contains an article by F. Hope Jones, on "The Electric Time-Service." See WATcn; TfiaE-SloNALs; TIME, STANDARD.