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At the beginning of 19th century Ino Tadataka surveyed almost whole coast lines of Japanese Islands and main roads, and made 214 sheet maps of 1:36000 and 8 sheet maps of 1:216000 in scale. This paper deals with his map compilation and scale-down. method. Almost every night, if possible. Ino measured elevation angles of 20 to 30 stars crossing meridian to determine latitude. The Y coordinates of the observation points were calculated from the latitudes using the ratio that one degree difference in latitude was 28.2 ri (or 101.52×36000 sun). Here ri and sun are Japanese old measures. Ino could not measure longitude astronomically because he had not chronometer. He corrected coordinates (x,y) obtained in surface survey "Dosen-Ho", a kind of open traverse method. The X coordinates of the observation points were estimated as x Y/y. In this way, he obtained coordinates (X,Y) on scale of 1:36000 concerning approximately 1220 astronomical observation points in whole Japanese Islands. For the first step, he prepared local maps of 1:36000 from local surface survey, then corrected them by using the coordinates of astronomical observation points. For second step. he compiled the wide area maps of 1:36000 from local maps to control reference to the coordinates of observation points. The maps of 1: 216000 were compiled from the maps of 1:36000 by using the reduced coordinate values of one six. In this process, the coordinates of the observation points were referred to keep precision of the maps. [ABSTRACT FROM AUTHOR]

Abstract: Lake Suigetsu, Honshu Island, Japan provides an ideal sedimentary sequence from which to derive a wholly terrestrial radiocarbon calibration curve back to the limits of radiocarbon detection (circa 60kabp). The presence of well-defined, annually-deposited laminae (varves) throughout the entirety of this period provides an independent, high resolution chronometer against which radiocarbon measurements of plant macrofossils from the sediment column can be directly related. However, data from the initial Lake Suigetsu project were found to diverge significantly from alternative, marine-based calibration datasets released around the same time (e.g. ). The main source of this divergence is thought to be the result of inaccuracies in the absolute age profile of the Suigetsu project, caused by both varve counting uncertainties and gaps in the sediment column of unknown duration between successively-drilled core sections. Here, a re-analysis of the previously-published Lake Suigetsu data is conducted. The most recent developments in Bayesian statistical modelling techniques (OxCal v4.1; ) are implemented to fit the Suigetsu data to the latest radiocarbon calibration datasets and thereby estimate the duration of the inter-core section gaps in the Suigetsu data. In this way, the absolute age of the Lake Suigetsu sediment profile is more accurately defined, providing significant information for both radiocarbon calibration and palaeoenvironmental reconstruction purposes. [Copyright &y& Elsevier]