Memoir on a Trans-Neptunian Planet, Memoirs of the Lowell Observatory Volume 1 No. 1, 1915. OFFPRINT [PREDICTION OF A PLANET BEYOND NEPTUNE: PLUTO]

Lynn, MA: Thos. P. Nichols & Son Co, 1915. 1st Edition. FIRST EDITION, OFFPRINT IN ORIGINAL WRAPPERS OF VOLUME I OF LOWELL'S PREDICTION OF THE EXISTENCE OF A PLANET BEYOND THE ORBIT OF NEPTUNE, here also calculating its probable position. 9 plates are included.

Lowell's 1903 hunch about the existence of a ninth planet led him, in 1905, to organize his observatory staff and task them with carrying out a systematic search for "a planet out there as yet unseen by man" (Lowell, Lowell Observatory, The Story of Pluto). Eleven years later, the product of that work was the mathematical, observational, and photographic studies he then published in 1915 - the work offered here -- Memoir on a Trans-Neptunian Planet.' While Lowell died the following year, his work survived his death and "culminated in 1930 with the discovery of Pluto at Lowell Observatory by Clyde W. Tombaugh" (Schindler, Pluto and Lowell Observatory).

"The first phase of Percival Lowell's hunt for Planet X ran from 1905 to 1909 . Lowell and his small team of 'computers'... carried out a series of calculations based on the observed perturbations of Uranus, pinpointing likely locations for the new planet . [In 1910] Lowell redoubled his mathematical efforts by incorporating the latest technology .With new calculations and improved equipment, Lowell estimated locations of Planet X and published his findings in the 1915 Lowell Observatory publication, Memoir on a Trans-Neptunian Planet.

"Unfortunately, Lowell died the following year, before he had a chance to complete a photographic search in the targeted area of the sky. Eleven years after Lowell's death, the final phase of the Observatory's search for Planet X commenced . Abbott Lawrence Lowell, Percival's younger brother and president of Harvard University, gave $10,000 for the construction of a new telescope, a 13-inch photographic instrument usually referred to as an astrograph. To operate the telescope, director V. M. Slipher hired a young man from Kansas of 'the self-made type,' Clyde Tombaugh. Tombaugh arrived in Flagstaff in 1929 and soon took over the systematic search for Planet X, examining the area of sky Lowell had indicated in Memoir on a Trans-Neptunian Planet. The 13-inch telescope was ideal for the search, and Tombaugh had the patience and attention to detail necessary for the work. On February 18, 1930, he discovered what would soon be named Pluto, completing the search begun by Percival Lowell 25 years earlier" (Schindler).

"More than any other astronomer of his generation, Percival Lowell (1855-1916) had a profound influence on the general public" (Dictionary of Scientific Biography, Vol. VIII, 521).

Volume II of Lowell's Memoirs, while not present here, considers a separate subject, the structure of Saturn's Rings. CONDITION & DETAILS: Thos. P. Nichols & Son Co, Lynn, MA. Complete with 9 plates, 2 double page. Large 4to. 12.25 x 9.75 inches (311 x 248mm.) [105], 5, [9 plates], 1. The wrappers are well-sunned and spotted, but are in good solid condition and remain tightly attached. The name "J. Brandt" is written in an early hand in the upper right corner of the front wrap. Inside the work exceptionally bright and clean with nice wide margins. The volume is housed in a red and black custom case, gilt-titled and -lettered at the spine.