From the Japanese book:
Keishichō Budō Kyūjū Nen-shi
(警視厅武道九十年史 - The 90-Year History of the Metropolitan Police Department’s Martial Arts)
Published in 1965 by the:
Keishichō Keimubu Kyōyōka Hen
(警視宁 警務部 教養課編 - Compiled by the Metropolitan Police Department, Training Division)
This book details the history of Police Martial arts training from 1874 to 1964.
"The history of martial arts within the Metropolitan Police Department is a long one. It is no exaggeration to say that it began with the establishment of the department itself on 15 January 1874, meaning that this year marks exactly ninety years of history. Spanning across the Meiji, Taishō, and Shōwa eras, the development of martial arts within the department has steadily progressed, making significant contributions not only to police martial arts but also to the advancement of Japanese martial arts as a whole.
In fact, during the difficult period for the martial arts community following the Meiji Restoration, it played a historic role in preserving martial traditions. Likewise, in the post-war period, it worked to maintain and sustain martial arts, laying the foundations for their present-day prosperity."
This is an important part of the history and develoment of Taiho-jutsu from the eraly Meiji era through to the Showa period.
It is especially interesting to me, as two of the earliest teachers:
Nakamura Hansuke Nakamura and Uehara Shōgo
were from the Ryōi Shintō-ryū Jūjutsu school, which I have practiced since 1976.