SHACKLETON 364 SHAFTER others in a whale boat, to South Georgia, 800 miles distant. After three failures, he finally succeeded in reaching the sur- vivors of the party. Three, however, had perished. During this expedition new land, named Kaird Coast, was discovered. Shackleton was knighted in 1909. He wrote "The Heart of the Antarctic," and "The Diary of a Troopship." SHACKLETON, ROBERT, an Ameri- can writer, born at Mazomanie, Wis., in I860. He was educated in the schools of Cleveland, Ohio, and studied law at the University of Michigan, being admitted to the bar in 1881. He was engaged in newspaper work in New York for several years and from 1900 to 1902 was asso- ciate editor of "The Saturday Evening Post." He wrote many books in col- laboration with his wife on antique fur- niture, and also books on miscellaneous subjects. Among these are "The Great Adventurer" (1904) ; "The Quest of the Colonial" (1907) ; "Adventures in Home- Making" (1910) ; "The Charm of the An- tique" (1914) ; "Touring Great Britain" (1914); "The Book of Philadelphia" (1919): "The Book of New York" (1917); "The Book of Chicago" (1920). SHAD, the popular name of three anadromous fishes of the genus Clupea: (1) The allice or European shad. (2) The American shad, C. sapidissima, an important food fish, abundant on the At- SHAD lantic coast of America, and in some of the American rivers. It spawns in fresh water. Great quantities are salted. (3) The Twaite shad, C. finta, from 12 to 16 inches long, with 21-27 stout osseous gill- rakers on the horizontal part of the outer branchial arch. Common on the coasts of Europe, ascending rivers; abundant in the Nile. The flesh is coarser than that of the allice shad. SHADDOCK (Citnts decumana) , some- times called pompelmoose, a large species of orange, attaining the diameter of seven or eight inches, with a white, thick, spongy, and bitter rind, and a red or white pulp of a sweet taste, mingled with acidity. It is a native of China and Japan, and was brought to the West In- dies by a Captain Shaddock, from whom it derived its name. In the United States they are grown for the market in Florida and California. Grapefruit or pomelo is a variety of shaddock. SHADOW. (1) Shade within defined limits; the figure of a body projected on the ground, etc., by the interception of light; obscurity or deprivation of ligblt, apparent on a surface or plane, and rep- resenting the form of the body which intercepts the rays of light. (2) Dark- ness, gloom, shade, obscurity. (3) The dark part of a picture; the representa- tion of comparative deficiency or depri- vation of light; shade. (4) A reflected image, as in a mirror or water, hence, any image or portrait. In optics, shadows are, theoretically considered, of two kinds, geometrical and physical. If a shadow be supposed to be produced by the interception of light pro- ceeding from a single mathematical point, it will be well defined by straight lines proceeding from the point, and grazing the intervening object. But as every luminous body is possessed of some mag- nitude, and, therefore, emits light from many points, the shadow is not precisely defined, but consists of a portion in per- fect shadow, or to which no luminous rays have access, and penumbra, to which some rays have access. In the former case the theoretical shadow is a geometric one, in the latter physical, i. e., such as actually occurs in nature. SHADWELL, THOMAS, an English dramatist; born in Stanton Hall, Nor- folk, England, about 1640. His comedy "The Sullen Lovers," produced in 1668, brought him reputation. Among many other plays, he was the author of "The Virtuoso" (1676); "Lancashire Witches" (1682) ; "The Squire of Alsatia" (1688) ; and "Volunteers; or, The Stock -Jobbers" (1693). He became poet-laureate and historiographer royal in 1688, succeeding Dryden in both positions. ("Works," 4 vols. 1720.) He died Nov. 20, 1692. SHAFROTH, JOHN FRANKLIN, a United States Senator from Colorado, born at Fayette, Mo., in 1854. He grad- uated from the University of Michigan in 1875 and in the following year was admitted to the bar. After practicing in Fayette, Mo., he removed to Denver. He was city attorney of that city from 1887 to 1891. In 1895 he was elected to Con- gress, and was re-elected until 1905. He was governor of Colorado from 1909 to 1911, and again from 1911 to 1913. In the latter year he became United States Senator, serving until 1919. SHAFTER, WILLIAM RTJFUS, an American military officer; born in Gales- burg, Mich., Oct. 16, 1835; at the out- break of the Civil War he entered the
