{"product_id":"tona-ワンプッシュクロノグラフtona-monopusher-chronograph-landeron-hahn-50-jumbo-1930ｓ","title":"TONA Monopusher Chronograph cal. Landeron Hahn 39 \/ 1930s Jumbo 39mm","description":"\u003cp\u003e— Across roughly a century —\u003c\/p\u003e\n\u003cp\u003eA 39mm case with the weight of age appropriate to its period, and Breguet indexes adding classical dignity.\u003c\/p\u003e\n\u003cp\u003eThe dense dial design, woven from a central snail tachymeter and a telemeter around the periphery, holds the eye and does not let it go.\u003c\/p\u003e\n\u003cp\u003eThe texture of hands and dial, weathered dry by the years, gives off a quiet beauty as evidence of having lived through its era, while the details speak for what makes a vintage chronograph worth having.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eA commanding 39mm oversize case carrying the history and weight of the 1930s. Fitted with the column-wheel Cal. Landeron HAHN 39, a calibre of the transitional period. A beautifully weathered porcelain dial and dignified Breguet numerals. A pairing of a low-speed snail tachymeter and a telemeter for distance. The Italian marking \"ACCIAO INOSSIDABILE,\" speaking for its history and scarcity.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e— Cal. Landeron HAHN 39 —\u003c\/p\u003e\n\u003cp\u003eCharles Hahn \u0026 Cie. was a watch movement maker in the Swiss canton of Neuchâtel.\u003c\/p\u003e\n\u003cp\u003eIn the 1920s it became known under the company name Landeron, and supplied movements under that name thereafter.\u003c\/p\u003e\n\u003cp\u003e— The significance of the Hahn calibres —\u003c\/p\u003e\n\u003cp\u003eWhat are called the Hahn calibres are the movements produced in Landeron's predecessor period.\u003c\/p\u003e\n\u003cp\u003eCal.39 is emblematic of the chronograph's early years — a transitional calibre showing the move from monopusher to two-pusher construction.\u003c\/p\u003e\n\u003cp\u003eIt has a column-wheel monopusher construction, controlling start, stop and reset from a single button: a mechanism that carries the breath of the chronograph's earliest era into the present.\u003c\/p\u003e\n\u003cp\u003eThe succeeding Cal.40 to 42 moved to two pushers, and in 1937 Cal.47\/49 changed over to cam actuation.\u003c\/p\u003e\n\u003cp\u003e— The \"acciaio\" marking —\u003c\/p\u003e\n\u003cp\u003e\"ACCIAO INOSSIDABILE\" struck on the caseback is Italian for a stainless steel case.\u003c\/p\u003e\n\u003cp\u003eSwiss watch specifications also sometimes read \"Cassa in acciaio inossidabile,\" indicating that the material is stainless steel.\u003c\/p\u003e\n\u003cp\u003e— The red scale on the porcelain dial —\u003c\/p\u003e\n\u003cp\u003eA red snail tachymeter is marked at the centre of the dial.\u003c\/p\u003e\n\u003cp\u003eAn ordinary tachymeter can only measure above 60 km\/h, whereas a snail tachymeter can also read the low-speed range below 60 km\/h.\u003c\/p\u003e\n\u003cp\u003e— How to use the snail tachymeter —\u003c\/p\u003e\n\u003cp\u003eStart the chronograph and stop it after one kilometre. The figure the seconds hand indicates on the spiral scale is the average speed.\u003c\/p\u003e\n\u003cp\u003ePatented in Switzerland in 1907, it was widely adopted on chronographs of the 1940s.\u003c\/p\u003e\n\u003cp\u003e— What the telemeter does —\u003c\/p\u003e\n\u003cp\u003eA red telemeter scale is marked around the periphery.\u003c\/p\u003e\n\u003cp\u003eFrom \"tele\" (far) and \"meter\" (measure), it is a scale for measuring distance.\u003c\/p\u003e\n\u003cp\u003eIt uses the difference in speed between light and sound: light arrives instantly, sound travels at about 340 m\/s, and the distance is calculated from the interval.\u003c\/p\u003e\n\u003cp\u003e— How to use the telemeter —\u003c\/p\u003e\n\u003cp\u003eStart the chronograph the instant you see the light — lightning, or gunfire — and stop it the instant you hear the sound.\u003c\/p\u003e\n\u003cp\u003eThe figure the seconds hand indicates on the telemeter scale is the distance in kilometres.\u003c\/p\u003e\n\u003cp\u003eIt was used in the First World War to measure the distance of shellfire; today it can be used more playfully, to measure the distance of lightning or fireworks.\u003c\/p\u003e","brand":"Other","offers":[{"title":"Default Title","offer_id":40554233135233,"sku":null,"price":468000.0,"currency_code":"JPY","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0555\/4313\/6385\/files\/IMG_20250926_120920.jpg?v=1764362381","url":"https:\/\/watchtenderjapan.com\/en\/products\/tona-%e3%83%af%e3%83%b3%e3%83%97%e3%83%83%e3%82%b7%e3%83%a5%e3%82%af%e3%83%ad%e3%83%8e%e3%82%b0%e3%83%a9%e3%83%95tona-monopusher-chronograph-landeron-hahn-50-jumbo-1930%ef%bd%93","provider":"WatchTender","version":"1.0","type":"link"}