Inō Tadataka

Ino Tadataka

fierst map

Inō Tadataka (伊能 忠敬 February 11, 1745 – May 17, 1818) was a Japanese surveyor and cartographer from Sawara. He is known for completing the first map of Japan created using modern surveying techniques. Refer from Wikipedia

He is the greatest person on Sawara  and is the one who made two different life.
His first life is that stayed at Sawara from 17 to 49 made big success as business man after that he made very first accurate Japanese map as a second life.
The retired 49-year-old, out into the Edo when the 50-year-old, and fit the astronomy-study of the calendar. Grasp the opportunity to start the making map, Over the course of the senior generation of spending17 years is surveying the whole of Japan, walking distance is 40000KM which about round trip earth.Create all the drawings by Japan for the first time measured.
At first his life until when he is 50 years old, when Tadataka came and took over business to Ino house, family business was weakening critical situation. Tadataka well as thorough thrift, in addition to the core business of brewing industry also may be provided firewood wholesaler in Edo, and the brokerage of rice traded, completely rebuild (in the case of 29-year-old of Ino house management in about 10 years annual revenues 351 Ryou = about 35 million yen now).It becomes a headman in the 36-year-old, in a large famine of Tenmei of 1783 (38 years old), and Nageu~tsu the private property is committed to the relief of the poor people of the region such as imparting the rice and money, the village of Tadataka have not issued even one of starvation It was. Ino House of revenue in 1793 (48 years) will increase up to the both 1264 Ryou (about 100 million 26.4 million yen now). During this time, as a hobby and enjoyed the study of the calendar in, Retirement and giving up all of the family business to his eldest son when hi is in 49 years old. He completely success as a business person on his first life.
As a Second his life when Out into the Edo  from Sawara when the 50-year-old, is poised to Fukagawa town, because of the calendar reform work for government the astronomer -Yoshitoki Takahashi set to astronomical side of the bannerman as a student but teacher Takaahshi Yoshitoki is 20years younger than Tadataka.
In addition to studying astronomy, study of the calendar, by providing a scale of observatory comparable to astronomical how at home, are eager to observe and advanced of the sun and stars, it was absorbed in the calculation of celestial navigation that breakthrough.
Order to observe Decide the time, is not like going out, it seems to have not can also speak slowly and not caught in the rain.
Because it is less enthusiastic, Yoshitoki teacher of Takahashi that wearing a “nickname” that “too much consideration teacher” to Tadataka. Tadataka is remodeled his home to full-fledged astronomical observatory follow by the first time a successful observation of the meridian passage of Venus in Japan.
During the study, Yoshitoki and Tadataka do want to know regarding the eclipse, for the accurate prediction of the lunar eclipse, that there is a difference of latitude one and a half minutes between his home Fukagawa and calendar stations of Asakusa became want to know the size of the Earth.
Yoshitoki mentioned such as that seeking distance of one minutes latitude by pacing between calendar stations is not long ennough if longer distance will become a reliable value measured in Hokkaido and Edo as more long distance, it was supposed to submit an application of Ezo surveying the shogunate thing.
Means Tadataka did not want to make Map, he want to know just how big the size of Earth.
Meridian once of length 25 ri, 30 ri,  or 32-ri was divided opinions between even astronomer So Tadataka proposed “We observed by two points the height of the North Star, look up to understand the difference of latitude by comparing the angle, if the distance of the two points is known Earth could calculate outer peripheral because the sphere”. Yoshitoki was agreed to draft Tadataka. For more distant if the two points farther error is reduced, that measure the distance from the Edo to Ezo (Hokkaido) it was desirable. But, you can not go to Ezo If there is no shogunate permit at the time.
Yoshitoki idea was nominal was “Map production” (by a clogged calendar production is the original purpose, map production was a pretext in order to obtain the freedom of movement). Around this time, to request a trade landed the Russian envoy in Ezo, has happened Russians landing incident, accurate map for national defense was necessary. Master and pupil of Yoshitoki -Tadataka butting there, resulting in shogunate not Ezo only, put the entire survey permit East makes Tadataka would have started making map first trip to EZO.
At 1800, when that was visiting the surveying of Ino Tadataka also Ezo, Mamiya Rinzo(Explore, he is the only Japanese person name on world map ) also Ezo investigation, speaking to Tadataka at the time and, not Could yet recognized the work to shogunate, Rinzo also, officials In collection is also can not get ahead, I was sent a day-to-day to do a silently work. Two people not in de samurai house sometimes circumstances were similar, Rinzo 21 years old, had been away Tadataka 56-year-old and the parent and child about a year, and hit it off immediately, and has signed a master and pupil relationship.At 1811 which Rinzo has returned from Sakhalin expedition to Edo, it reunited with again Tadataka. Around this time, Tadataka is for making a map of Japan, had been carried out a large business that surveying the whole country. To Rinzo you played a reunion, Tadataka ask the survey of “Ezo”. Tadataka already only of old age, a survey of harsh Ezo, I was entrusted to Rinzo is an expert of northern exploration. Rinzo is then multiplied by spending10years, was around on by surveying the Ezo whole area. Without the work of this Rinzo, would not have completed of Tadataka Japanese map.


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