The Japanese optical industry started with the outbreak of World War One when the import of the optical weapons was suspended. The Imperial Japanese Navy made a decision to produce them domestically. The optical factory of the Naval Arsenal in Tsukiji succeeded in making an original rangefinder for preproduction purposes. In this paper, I would like to discuss the technology transformation process of the Japanese optical industry by verifying the technological progress of Japanese rangefinders. The database of the Industrial Property Digital Library is used. The early composition of the Japanese optical industry was the Naval Arsenal factory and two private companies closely associated with the government (i.e. Nippon Kogaku K.K. and Tokyo Gasu Denki K.K.). The new optical design technology (ray tracing method) was introduced to the Naval Arsenal by Kogoro Yamada from England independently from the German engineers whom Nippon Kogaku K.K. invited. However, due to the disarmament by the Washington Naval Treaty, the Naval Arsenal was closed and the optical factory of Tokyo Gasu Denki K.K. was also shut down despite its high technological level. As a result rangefinder and optical glass manufacturing technology was transferred to Nippon Kogaku K.K. from the Naval Arsenal which became a single powerful optical company. It was made clear in this paper that the technological level of the Japanese optical industry was self-reliant by early the Showa era through close cooperation between military, industry and academic.

View full abstract

Isaac Beeckman (1588-1637) is a self-learning man. He learned medicine by his reading medical books (contemporary and classic). In this paper I study how Beeckman read and understood them. He did not merely memorize them. But he gave some supplementary explanations to their (he thought) insufficient passages, sometimes criticized them and gave mechanical explanation that was based on atomism with hydrostatics. We can find similar ways of reading in the works of Lucretius and Cardano which young Beeckman read repeatedly. Beeckman learned the way of explaining natural phenomena with atomism from Lucretius' De rerum natura, and the way of explaining mechanics with natural philosophy and of demonstrating the principles of natural philosophy with machines from Cardano's De subtilitate. Beeckman's interactive reading is a good style of self-learning, but to avoid some bad effects of self-learning, he had to talk actually to a good respondent such as young Descartes.

View full abstract

During the past half a century archaeologists in China excavated some paper-like remnants dating from the Western Han Dynasty. Based on these findings, Pan Jinxing proposed that paper was invented before Ts'ai Lun, doubting on his contribution to the invention of papermaking technology. With the publication of new Academic Journal named "Paper History Study", China Technical Association of the Paper Industry Society members strongly opposed his opinions by re-analyses all of the unearthed papers and historical references. The major counter-evidences are as follows: a. there existed mis-judgments on produced ages of unearthed papers or paper-like objects, b. Some of the unearthed papers reported were not paper but paper-like objects made of botanical fibers bundles due to natural force or primitive paper-like models and the stormy discussion was made on the definition of paper, c. there are referential supports on the Ts'ai Lun's originality on the invention of papermaking. These conclusive remarks expressed by the Association of Paper Industry were compared with those of Pan Jinxing in the form of the table. The final conclusion on the existence of "the papers before Ts'ai Lun", therefore, must await further scientific analyses by the disinterested party.

View full abstract