Hand (unit) divided by four, then the remainder is added after the radix point. Thus, a horse that measures 60 inches is 15 hands high (15 x 4 = 60) and a horse halfway between 15 and 16 hands is 15.2 hands, or 62 inches tall (15 x 4 + 2 = 62) Because the subdivision of a hand is a base 4 system, a horse 64 inches high is 16.0 hands high, not 15.4. A designation of "15.5 hands" is not halfway between 15 and 16 hands, but rather reads 15 hands and five inches, an impossibility in a base 4
Hand-Held Maneuvering Unit use his HHMU on Gemini 11, because his EVA had to be cut short when he became fatigued. Hand-Held Maneuvering Unit The Hand-Held Maneuvering Unit (HHMU), also known as the maneuvering gun, or informally as "the zip gun", was used by astronaut Ed White in the first American "spacewalk" (extra-vehicular activity, EVA), on Gemini 4, June 3, 1965. Different models of HHMU were present on Gemini 4, 8, 10, and 11, but were only used on Gemini 4 and 10. It was also used aboard Skylab. Astronauts described the gun as easier to use than other methods of maneuvering during