John Arnold (watchmaker) wore it and carried it around. The watch exceeded all expectations, as it demonstrated great accuracy. The timekeeping error was 2 minutes 32.2 seconds, but the error in the last nine months amounted to just one minute. The greatest error in any 24 hours was only four seconds, or one nautical mile of longitude at the equator. Subsequently, Arnold produced a pamphlet that detailed the trial and results, with attestations of veracity from all those concerned with the tests. Maskelyne's assistant, the Rev. John Hellins, was in charge of the pamphlet. The astonishing performance of this watch caused controversy, because
Longitude of the periapsis with part of it being measured in the plane of reference and the rest being measured in the plane of the orbit. Likewise, any angle derived from the longitude of periapsis (e.g., mean longitude and true longitude) will also be compound. Sometimes, the term "longitude of periapsis" is used to refer to "ω", the angle between the ascending node and the periapsis. That usage of the term is especially common in discussions of binary stars and exoplanets. However, the angle ω is less ambiguously known as the argument of periapsis. "ϖ" is the sum of the longitude of ascending node