devote one of the telescopes of the observatory to stellar photometry, and after an exhaustive trial of various forms of photometers, he devised the meridian photometer (see Photometry, Stellar), which seemed to be free from most of the sources of error. With the first instrument of this kind, having objectives of 1.5 inch aperture, he measured the brightness of 4260 stars, including all stars down to the 6th magnitude between the North Pole and –30° declination. With the object of reaching fainter stars, Professor Pickering constructed another instrument of larger dimensions, and with this more than a million observations have been made. The first important work undertaken with it was a revision of the magnitudes given in the Bonn Durchmusterung. On the completion of this, Professor Pickering decided to undertake the survey of the southern hemisphere. An expedition, under the direction of Prof. S. I. Bailey, was accordingly dispatched (1889), and the meridian photometer erected successively in three different positions on the slopes of the Andes. The third of these was Arequipa, at which a permanent branch of the Harvard Observatory is now located. The magnitudes of nearly 8000 southern stars were determined, includ1ng 1428 stars of the 6th magnitude and brighter. The instrument was then returned to Cambridge (U.S.A.), where the survey extended so as to include all stars of magnitude 7.5 down to –40° declination, after which it was once more sent back to Arequipa. In 1886 the widow of Henry Draper, one of the pioneers of stellar spectroscopy, made a liberal provision for carrying on spectroscopic investigations at Harvard College in memory of her husband. With Professor Pickering's usual comprehensiveness, the inquiry was so arranged as to cover the whole sky, and with four telescopes—two at Cambridge for the northern hemisphere, and two at Arequipa in Peru for the southern—to which a fine 24-in. photographic telescope was afterwards added, no fewer than 75,000 photographs had been obtained up to the beginning of 1901. These investigations have yielded many important discoveries, not only of new stars, and of large numbers of variable stars, but also of a wholly new class of double stars whose binary character is only revealed by peculiarities in their spectra. The important conclusion has been already derived that the majority of the stars in the Milky Way belong to one special type.
PICKERING, TIMOTHY (1745-1829), American politician,
was born at Salem, Massachusetts, on the 17th of July 1745.
He graduated from Harvard College in 1763 and was admitted
to the bar in 1768. In the pre-revolutionary controversies he
identified himself with the American Whigs; in 1773 he prepared
for Salem a paper entitled Stale of the Rights of the Colonists, in
1775 he drafted a memorial protesting against the Boston Port
Bill, and in 1776 he was a representative from Salem in the
General Court of Massachusetts In 1766 he had been commissioned
lieutenant and in 1769 captain in the Essex county
militia, early in 1775 he published An Easy Plan of Discipline
for a Mzlztza adopted in May 1776 by the General Court for use
by the militia of Massachusetts, and he was elected colonel of
his regiment. In the same year he became judge of the court
of common pleas for Essex county, and sole judge of the maritime
court for the counties of Suffolk, Essex and Middlesex. In the
winter of 1776-1777 he led an Essex regiment of volunteers
to New York, and he subsequently served as adjutant-general
(June 1777-]an. 1778) and later as quartermaster-general
(1780- 1785), he was also a member of the board of war from the
7th of November 1777 until its abolition. With the aid of some
officers he drew up, in April 1783, a plan for the settlement of
the North-West territory, which provided for the exclusion of
slavery In 1785 he became a commission merchant in
Philadelphia: but in October 1786, soon after the legislature of
Pennsylvania had passed a b1ll for erecting Wyomiug district
into the county of Luzerne, he was appointed pro tho notary and
a judge of the court of common pleas and clerk of the court of
sessions and orphans' court for the new county, and was commissioned
to organize the county. He offered to purchase for
himself the Connecticut title to a farm, and in the following year
he was appointed a member of a commission to settle claims
according to the terms of an act, of which he was the author,
confirming the Connecticut titles (see WYOMING VALLEY and
WILKES-BARRE). Pickering was a member of the Pennsylvania
convention of 1787 which ratihed the Federal constitution. and
of the Pennsylvania constitutional convention of 1789-1790.
In November 1790 he negotiated a peace with the Seneca
Indians, and he concluded treaties with the Six Nations in July
1791, in March 1792 and in November 1794. Under Washington
he was postmaster-general (1791-1795), secretary of war (1795),
and after December 1795 secretary of state, to which position he
was reappointed (1797) by Adams. In 1783, while he was
quartermaster-general, he had presented a plan for a military
academy at West Point, and now, as secretary of war, he supervised
the West Point military post with a view to its co11version
into a military academy. As head of the state department
he soon came into conflict with Adams. His hatred of France
made it impossible for him to sympathize with the president's
efforts to settle the differences with that country on a peaceable
basis. He used all his influence to hamper the president and
to advance the political interests of Alexander Hamilton,
until he was dismissed, after refusing to resign, in May 1800.
Returning to Massachusetts, he served as chief justice of the
court of common pleas of Essex cou11ty in 1802-1803. He was
a United States senator in 1803-1811 and a member of the
Federal House of Representatives in 1813-1817. As an ultra
Federalist-he was a prominent member of the group known
as the Essex ]unto-he strongly opposed the purchase of
Louisiana and the War of 1812. He died at Salem, Massachusetts,
on the 29th of January 1829.
The standard biography is that by his son, Octavius Pickering (1791-1868), and C. W. Upham, The Life of Timothy Pickering (4 vols., Boston, 1867-1873). In the library of the Massachusetts Historical Society at Boston, there are sixty-two manuscript Volumes of the Pickering papers, an index to which was published in the Collections of the society, 6th series, vol. viii. (Boston, 1896).
His son, John Pickering (1777-1846), graduated at Harvard in 1796, studied law and was private secretary to William Smith, United States minister to Portugal, in 1797-1799, and to Rufus King, minister to Great Britain, in 1799-1801. He practised law in Salem and (after 1827) in Boston, where he was city solicitor in 1827-1846, and wrote much on law and especially on the languages of the North-American Indians. He was a founder of the American Oriental Society and published an excellent Comprehensive Dictionary of the Greek Language 1826).
See Mary O. Pickering (his daughter), Life of John Pickering (Boston, 1887).
Timothy Pickering's grandson,Charles Pickering (1805-1878), graduated at Harvard College in 1823 and at the Harvard Medical School in 1826, practised medicine in Philadelphia, was naturalist to the Wilkes exploring expedition of 1838-1842, and in 1843-1845 travelled in East Africa and India. He wrote The Races of Man and their Geographical Distribution (1848), Geographical Distribution of Animals and Man (1854), Geographical Distribution of Plants (1861) and Chronological History of Plants (1879).
PICKERING, a market town in the Whitby parliamentary division of the North Riding of Yorkshire, England, 32 m. N.E. by N. from York by the North Eastern railway, the junction of several branch lines. Pop. of urban district (1901), 3491. The church of St Peter is Norman and transitional Norman, with later additions including a Decorated spire. It contains a remarkable series of mural paintings of the 15th century. The castle, on a hill to the north, is a picturesque ruin, the fragmentary keep and several towers remaining. The work is in part Norman, but the principal portions are of the 14th century. One of the towers is connected in name and story with Fair Rosamond. The castle was held by Earl Morcar shortly before the Conquest; it then came into the hands of the Crown, and subsequently passed to the duchy of Lancaster. It was the prison of Richard II. before his confinement at Pontefract. During the civil wars of the 17th century the castle was held by the Royalists, and suffered greatly in siege. The district