Bunsen and KirchhoflE. and the first attempt to classify the stars according to their spectra. While engaged in making his observations upon star- spectra Mr. Rutherford discovered the use of the star-spectroscope to show the exact state of achromatic correction in an object-glass, particularly for the rays that are used in photography. In 1864, after many experiments in other directions but for the same end. he Mieeeeded in devising and constructing an objective of Hi inches aperture and about 15 feet focal length, corrected for photography alone. This objective was a great suc- cess, and was in constant use in making negatives of the sun, moon, and star-groups, until it was replaced in 1868 by another, which had about the same focal length but was 13 inches in aperture. This glass was an ordinary achromatic, such as is used for vision, and was converted into a photo- graphic objective by the addition of a third lens of Hint glass, which made the proper correction and could be affixed in a few minutes. Mr. Rutherfurd constructed a micrometer for the measurement of astronomical photographs, for use. upon pictures of solar eclipses or transits and upon groups of stars, of which he has measured several hundred, showing, as he claims, that the photographic method is at least equal in accuracy to that of the heliometer or filar-micrometer, and far more convenient. The photographs of the moon made by Mr. Rutherfurd are of remarkable beauty and have not yet been surpassed. A German writer having suggested that the collodion film was not reliable. Mr. Rutherfurd published in 1872 a series of measurements that conclusively demonstrated its fixity under proper conditions. In 1804 he pre- sented to the National academy of sciences a photograph of the solar spectrum that he had obtained by means of bisulphide of carbon prisms. It con- tained more than three times the number of lines that had been laid down within similar limits on the chart by Bunsen and Kirchhoff. He construct- ed a ruling-engine in 1870 which produced interference-gratings on glass and speculum metal that were superior to all others until the recent productions of Prof. Henry A. Rowland. With one of these gratings, containing about 17,000 lines to the inch, he produced a photograph of the solar spectrum which was for a long time unequalled. In 1876 he published a paper describing an instrument in which the divided circle was of glass and showed by readings that it gave a far greater accuracy than could be obtained from divisions on metallic circles of the same dimensions. Mr. Rutherfurd was named by the president of the United States one of the American delegates to the Inter- national meridian conference that met in Washington in October, 1885, and he took an active part in the work and framed and presented the resolution that finally expressed the conclusions of the conference. He was invited by the French academy of sciences to become a member of the International conference on astronomical photography in Paris in 1887, and was appointed by the president of the National academy of sciences as its representative, but was obliged to decline on account of failing health. In 1858 he became a trustee of Columbia, but he resigned in 1884, after giving his astronomical instruments to that institution, in whose observatory they are now mounted. Mr. Rutherfurd was one of the original members named in the act of congress in 1863 creating the National academy of science, and was an associate of the Royal astronomical society, and his work had been recognized by the gift of many diplomas, memberships, orders, and medals, both domestic and foreign.
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RUTLEDGE, John, statesman, b. in Charleston, S. C., in 1739; d. there, 23 July, 1800. He was the eldest son of Dr. John Rutledge, who came to South Carolina from the north of Ireland about 1735, practised medicine in Charleston, and married a lady of fortune, leaving her a widow with seven children at the age of twenty-seven. The son, who was sent to England to study law at the Temple, returned to Charleston in 1761, and acquired a high reputation as an advocate. He was an earnest opponent of the stamp-act when it was discussed in the provincial assembly, was sent to the congress at New York in October, 1765, and with his colleague, Christopher Gadsden, boldly advocated colonial union and resistance to oppression. He was a member of the South Carolina convention of 1774, in which he argued in favor of making common cause with Massachusetts, and carried a resolution that South Carolina should take part in the proposed congress, and that her delegates should go unhampered by instructions. He was one of those that were chosen by the planters to represent them in the first Continental congress at Philadelphia, Patrick Henry pronounced him “by far the greatest orator” in that assembly. In 1775 he was again chosen a delegate to congress. He was chairman of the committee that framed a constitution for South Carolina in 1776, and on 27 March was elected president of the new government, and commander-in-chief of the military forces. When the British fleet arrived in Cape Fear river he fortified Charleston, and insisted on retaining the post on Sullivan's island when Gen. Charles Lee proposed its evacuation. During the battle he sent 500 pounds of powder, and directed Col. William Moultrie not to retreat without an order from him, adding that he would “sooner cut off his right hand than write one.” He was dissatisfied with changes in the constitution, and in March, 1778, resigned his office, but in the following year he was chosen governor again by an almost unanimous vote of the legislature, superseding Rawlins Lowndes. He was clothed with dictatorial powers, and prepared to repel the British invasion. When Gen. Augustine Prevost advanced upon Charleston in May, 1779, the city was defenceless. Gen. Benjamin Lincoln with the Continental troops being 150 miles away. The latter hastened to the succor of Charleston by forced marches, and state troops were gathered for the same object. It was proposed by the governor's council that the British should retire, on condition that South Carolina should remain neutral during the rest of the war, and that her fate should be determined by the issue of the conflict. This measure, which the historian Ramsay thinks was a ruse, devised for the purpose of gaining time, was favored by Rutledge, but opposed by Gadsden, the younger Laurens, and Moultrie. On Lincoln's approach, the enemy retreated, and Rutledge, at the head of the militia, took the field against the invaders.
