著者

佐々木 勝浩

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.4, pp.31-40, 1981

---

The Foucault's Pendulum in the National Science Museum was replaced by a new improved model in January-April 1981. Before that, some theoretical investigation and experiments, such as measurements of the damping rate and elliptical motion were carried out. We have compared two kinds of suspension. One is the "bolt type" in which the upper end of the wire is simply fixed by a bolt. Another is the "knife edge type" in which the wire is suspended by a ring equipped with double knife edges. The measurements of both the damping rate and the elliptical motion of the pendulum showed that the knife edge type is slightly better. In consideration of the result of the experiments, the bob and the wire changed in size and material, and the suspension ring was improved. The length of the new pendulum is 1950 cm, about 50 cm than before, and the new bob was made of stainless steel instead of lead. Stainless steel is less dense than lead but it is more suitable for the precise shaping and fine finish. The new bob is 23 cm in diameter, 3 cm longer than the old one. The writer designed a new suspension ring to increase the rigidity as shown in Figure 4. The formance of new pendulum is almost satisfactory but no remarkable decrease of damping rate and elliptical motion were observed.

著者

大迫 正弘

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.28, pp.1-11, 2005-12

---

Late in the 19th century two earthquakes struck northeastern Honshu at an interval of two years. The Imperial Earthquake Investigation Committee reported on the 1894 Shonai Earthquake, including many handwritten copies from photographs in the form of blueprints or dry plates, which are now kept in the collection of the National Science Museum. In contrast, fewer photographs of the 1896 Riku-u Earthquake are left in the collections. This was the case for the investigations of the earthquake at that time, although the event showed interesting phenomena in seismology, such as apparent faults. Afterwards, Dr Akitsune Imamura made a report of the Riku-u earthquake, introducing photographs in an album donated from an individual. This rare material is also preserved in the NSM.

著者

前島 正裕

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical Sciences & Engineering (ISSN:03878511)

巻号頁・発行日

no.20, pp.23-37, 1997

---

The development process of the radar technologies in Japan consisted of four stages as (1) at a dawn before 1941,(2) inspection tour to Germany in 1941,(3) beat with gun radar and (4) out of gear. Through this stage, each kind of radar was made by The Naval Technology Laboratory. A 10 cm magnetron was developed individually on the first stage. A application of radar system came from Germany. However some gun radars had been reproduced based on US and UK radar. The Finally a technological innovation was not happened.

著者

佐々木 勝浩

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.26, pp.21-31, 2003-12

---

Rokoku is the water clock used in ancient China, and the origin goes back to thousands years ago. The multistage type Rokoku which has several vessels as the typical form can be mentioned, and the first vessels is for water supply, the middle vessels are for control of flow rate of water, and the last vessel is for time measurement. The last vessel has a float with the time scale which we can read and know time. Although researches of J. Needham or D. Price were known, the sufficient interpretation about the accuracy and the usage of Rokoku as a clock was not carried out. In this research, first the physical character of a single vessel was observed, subsequently the change of the water level of each vessel was calculated numerically, and then the static and dynamic characteristics of Rokoku were examined. Consequently, in multistage type Rokoku it was able to confirm that the vessels play an important role in controle of a water flow, a fixed quantity of water is supplied periodically when actual using, for example 2 times everyday (in the morning and in the evening), and in the case of that sufficient accuracy is secured, etc.

著者

前島 正裕

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.28, pp.13-20, 2005-12

被引用文献数

2

---

The faradization apparatuses in Meiji Era played an important part for the history of electrification in Japan. However there are few data about machines, makers of them, amount of productions and etc. Investigating circuits, structures, dimensions of these machines and unique characters, this research offers some basic data about three machines of battery type and about two Magneto-Electric Machines that were preserved in the Edo-Tokyo Museum, the Toyota Commemorative Museum of Industry and Technology and the National Science Museum. Three battery machines were made by each makers individually in Japan but their structures were very similar. Two Magneto-Electric Machines made by foreign makers were in the same situation too.

著者

斎藤 修啓 鈴木 一義

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.21, pp.9-57, 1998

---

Tanahashi Library is located in the library of National Science Museum. Gentaro Tanahashi's bequest was presented by his wife Syou Tanahashi. The Catalog of Tanahashi Library comprises 654 items, which are arranged in 7 categories by authors. As follows : 1) 99 Books and booklets, 2) 87 periodicals, 3) 64 museum's guides, 4) 141 manuscripts, notes and memorandums, 5) 21 photos and postcards, 6) 118 materials related to museum, and 7) 124 other materials.

著者

洞口 俊博 平田 龍幸

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.15, pp.13-24, 1992

---

The Be stars in the young open cluster NGC663 were observed photometrically in 1989 and 1990 to study the evolutionary status of Be stars. The V magnitudes and colors of B-V are U-B presented and compared with the observations in previous papers

著者

西城 恵一

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.12, pp.21-27, 1989

---

In order to develop our previous works for Mira type variables (SAIJO and WATANABE, 1987; SAIJO, 1988), the period and magnitude of 21 semiregular variable stars are studied by using return maps. According to our previous works, return maps are classified into three types, Type 1,Type 2 and Type 3. Analysis on the period shows similar result to Mira type stars, which means that nearly all the semiregular stars belong to Type 3. Analysis on the magnitude shows that semiregular stars belong to two Types, Type 1 and Type 3. Discussion is also given.

著者

佐々木 勝浩 渡辺 誠

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.19, pp.17-42, 1996

---

The large Pillar clock with detailed hour scale 'SEIMITSU-SHAKUDOKEI' has been exhibited at the National Science Museum on loan from Mr. Shingo Takabayashi, on the scale of which has quite rare hour system, 13 deviding hour system, including special hour 'YO-JI', chinese character 'YO(餘)' of which means the remainder. In the historical investigations about astronmy in Ishikawa and Toyama prefecture, Watanabe, one of the authors, found the fact that the 13 deviding hour system was used in the old fief of Kage in Edo period. Also Watanabe and others found the astronomical clock 'SUIYOU-KYUGI' at the 'KOJU-BUNKO' library in Sinminato City. In examining the relation between the 'SEIMITSU-SHAKUDOKEI' and the 'SUIYOU-KYUGI', the evolution of hour system including rare hour 'YO-JI' in the old fief of Kaga was known in details. We report about this special hour system and discuss about the meaning of special hour 'YO-JI'.

著者

西城 惠一

出版者

国立科学博物館

雑誌

Bulletin of the National Science Museum. Series E, Physical sciences & engineering (ISSN:03878511)

巻号頁・発行日

vol.23, pp.1-25, 2000

---

Investigation of Japanese celestial globes made in Edo era tell us the development and popularization of Japanese astronomy during Edo era. We have the largest collection in Japan in National Science Museum, eight of about fity known celestial globes. In this paper, I study three globes from our collection, which considered to be made by Harumi SHIBUKAWA, known to be first astronomer of Edo era. Discussions are also given by comparing them with other known celestial globes studied before.