r Exists and Wha

ed to obtain a perfect rate between the two extremes, manufacturers gene

so at the two extremes and there will always be a few

to four seconds in the higher grades of steel bra

ong been known as the middle temperature error and for many years was one of the most

the error but they were always too infinitely complicated to be of commercial or

entirely to the fact that these distortions are not exactly equal in both directions. The free ends of the rims are drawn outward from the concentric form to a sli

lances Overcome the Mi

teel have been found to almost eliminate the middle error, which is reduced to one se

uipped with these balances and they have been adopted for commercial us

es, but owing to the necessary high cost of production, their general use may be delayed for some years to come. Their general use however w

ade necessary by the fact that the coefficient of nickel steel is about ten times less than that of ordinary steel, and if the cuts were made close to t

me ends and more nearly equalizing the extent of curvature both ways from the concentric form. This equalization is

or than the ordinary steel brass balance, but owing to the unstable nature of the metal th

g time from commercial watches but its influence is apparent in timing and it will there

RT

TO ISOCHRONIS