First, the round blanks for wheels are cut from strips of sheet brass. A brass ribbon as wide as the wheel is fed into a machine. A steam hammer with a die on the end as round and sharp-edged as a cooky cutter, comes down and cuts out little brass "cookies" that look like very thin, bright, telephone slugs.
Watch wheels all have holes in the middle like some cookies, and teeth or scallops around the edges. The hole is drilled first, and a number of blanks are strung on a rod like fiat beads on a string. Then the rod is clamped into a lathe. The operator slips a belt over the wheel—whir-r-r, how it hums! A steel chisel cuts a row of teeth up and down in all the blanks at once. Click, the rod turns a little and another tooth is cut.
A screw-making lathe clips a tiny bit of brass wire from a coil, whirls it under a chisel to point one end, strikes a blow that flattens the other end into a head, and saws a slot across the head for the screwdriver. Then a fairy chisel cuts a thread—like spiral groove from near the head down to the tapering tip. When it is done it isn’t much bigger than a little brown seed. Hundreds of them can be put into a pill box, or a one-ounce bottle.
In a watch factory are big fire-clay ovens, or kilns, as there are in potteries, for baking—what do you suppose? The white china dials. Some dials are gilded or plated with gold, but most of them are enamelled on copper plates with fine white porcelain from the pottery. The wet clay paste, or dough, is spread on the dial plate, baked in the oven, ground down smooth and glazed. When they come out of the oven they shine like frosted cakes. A pattern printed on a fine transfer paper is laid carefully on the dial and pasted smooth. Into the oven it goes again. The paper is burned up but the pattern is burned in. The dial of papa’s watch and your pretty china break- fast cup are decorated in much the same way.
The most delicate parts of a watch are the springs—the main-spring and the hair-spring. They are tiny ribbons and hairs of blue steel, so flexible that they can be coiled up tight, but so strong they can pull the wheels along. They are made of steel wire, ironed or rolled out flat, tempered by heat and cold, "blued," and with rivet holes bored in the ends. In a watch you can see the main spring beat and throb like a little live heart.
Machines make all the parts of a watch more perfectly and hundreds of times faster than men could make them by hand. But no machine can put all the parts of a watch together. A skilled
