This paper deals with a string of gravity measurements conducted by TANAKADATE Aikitu(1856-1952), one of the first graduates from the College of Science, University of Tokyo. These measurements were conducted with no substantial help from the Western scholars in the 1880s, when approximately only a decade had elapsed since the beginning of full introduction of Western sciences into Japan, and only a couple of years had passed since Tanakadate's graduation from the college. The aim of the measurements, the hypothesis considered prior to each measurement, and the manner of dealing with the data acquired are clarified to the maximum possible extent by careful examination of the existing documents. Some common features are found in their studies when compared with those conducted by the Western researchers at the same period. Tanakadate and other Japanese scientists, who worked with him, aimed at confirming their hypothesis that the gravity anomaly around the Japan islands should be positive. The gravity anomaly at Bonin island, in particular, was known to be the largest in the world and a geodesic or geophysical explanation for this was expected. When Tanakadate became aware of the anomaly, he considered that it could be caused by 'some failure in measurements', which led him to attempt a second measurement of the gravity at the same point. On the other hand, scholars in Europe had already acknowledged that gravity anomalies on isolated islands were generally larger than those observed on the continents and along the coasts, and no longer raised any doubt regarding the reliability of the data provided on isolated islands. They subsequently tried to determine the geophysical cause of the large anomalies and attempted to invent a suitable method for reducing the data, while Tanakadate and other Japanese researchers never applied the necessary reduction techniques to the data they had obtained.
This paper analyzes the development and use of visual tools known as "family trees" that allow medical practitioners to see hereditary family diseases. Family trees, consisting of family names and a tree diagram on personal traits, became popular among neurologists during the late 19th century. However, social scientists have devoted only scant attention to the historical and social processes through which, before the rediscovery of Mendelian laws, medical practitioners came to use family trees as scientific devices for nosographical classification of hereditary diseases, such as hereditary chorea(one of the initial terms used to describe Huntington's disease). The purpose of this paper is to trace the complex processes by which family histories, namely the descriptive nosography of family members, and family trees became distinct during the late 19th century. This paper argues that family trees of hereditary chorea became an important clinical tool, with the establishment of teaching hospitals, although, in the case of hereditary chorea, family trees were used to support different interpretations of the notion of heredity. The use of family trees was made possible by three conditions including the centralization of medical care, the standardization of medical records, and the circulation of medical information among medical practitioners.