Aiki (martial arts principle) and its practice is often kept within a particular individual or two from a family/school lineage. Culturally, and due to certain necessities of the time period, the aiki knowledge was usually a very well guarded secret and rarely disclosed. The oldest book to have historically discuss aiki was the 1899 Budo Hiketsu-Aiki no Jutsu. On the subject of aiki it was written: The Textbook of Jujutsu (Jujutsu Kyoju-sho Ryu no Maki) from 1913 wrote: Aiki (martial arts principle) Aiki from a Japanese budo term, at its most basic is a principle that allows a conditioned practitioner to negate or redirect
What Bird is That? according to their usual habitat. The accompanying text included brief notes on distribution, breeding and behaviour. While initial sales were poor, history tells us that Cayley had accurately discerned a market need and successfully responded to it. During WWII sales accelerated and Cayley’s first collection, reprinted time and time again, eventually became a household name among birdwatchers and the book was recognised as an Australian classic. The original sponsorship of "What Bird is That?" proved a great investment for the Gould League, who benefited from the sale of its numerous reprints and revised editions. By 1960, it was rated the