National Geographic : 1942 Feb
AMERICA'S DEFENSE MOVES FORWARD ON TIME! LIGHT AND LIGHTNING-FAST, these deadly little mosquitoes (P. T . boats) dart ahead of the fleet to harry the enemy. They can go 50 knots in rough seas... they carry torpedoes to humble the proudest ship afloat. For them, Hamilton is making tough and sturdy chronometer watches that are marvels of precision. EVER WATCH A DOCTOR time a blood coagulation? He draws a drop of blood into a frail glass tube. Every 15 seconds he breaks off a section. If the blood coagulates in less than 51 minutes, he knows it's safe to operate. Only one of the many vital uses for Hamilton's accurate time-keeping on the home front. "Mention the Geographic-It identifies you."