138 GR^VIUS while many others have failed. On the con- tinent of Europe they were first made auto- matic, and other improvements were also made in them. Gambey of Paris has so arranged his as to divide an instrument without any ec- centricity, even when placed in a slightly ec- centric position on the engine. Oertling of Berlin has an arrangement for correcting any original errors in the teeth while dividing, and other mechanists of celebrity have constructed them to suit their own views, and for their own use. In the United States there is a large one belonging to the coast survey, made by Simms of London, and afterward made auto- matic by Saxton; also one in Philadelphia made by Young, and one in New York by the Messrs. Blunt, both of which are automatic. There'is no branch of the mechanic arts which requires more skill in the use of tools, more geometrical knowledge, and greater patience, than the construction of a circular dividing engine. The large astronomical instruments are divided in a different manner, and, unless placed on a large engine from which the divi- sions may be in a manner copied, are original divisions. Troughton, Simms, and Jones of London have used movable microscopes with micrometers; while others on the continent of Europe have availed themselves of the feeling lever, a powerful instrument for that purpose invented by the astronomer Bessel. Straight line divisions for scales, &c., are made by means of a screw, a milled roller, or a wedge which is employed to move a platform sliding freely beneath a cutting frame, and carrying the scale to be divided. In the use of the screw much depends on its accuracy, and, with re- gard to the roller or wedge, on the working or manner of applying them. When great ac- curacy is required, the divisions are tested by means of two microscopes, and an error can be detected of j^Vor f an inch. The ruling ma- chines used by engravers in this country are well calculated for this purpose. GH KYII'S, Johann Georg (GRAEFE), a German scholar, born in Naumburg, Jan. 29, 1632, died in Utrecht, Jan. 11, 1703. He had begun to study law at Leipsic, when, meeting with Gronpvius at Deventer, he determined to be- gin his education over again, devoting himself to belles-lettres. After remaining two years at Deventer, he passed to Amsterdam, where he studied history under Morus and Blondel, and abjured Lutheranism for Calvinism. In 1658 he succeeded Gronovius in the athengeum of Deventer, and in 1661 obtained the chair of eloquence in the academy of Utrecht, to which was attached in 1667 that of politics and his- tory. Louis XIV. gave him a pension, and the mmvrsitk-s of Bddelbere. Leyden, and Padua in vain sought to attach him to them. Among his works are editions of Hesiod, Cicero, Ca- tullus. Til.iillus, I'ropi-rtius, Suetonius, and Flo- rus, and Thesauri of Italian antiquities. GRAFE. I. Karl Ferdinand von, a German sur- geon, born in Warsaw, March 8, 1787, died in GRAFTING | Hanover, July 4, 1840. He graduated as a doctor of medicine at Leipsic in 1807, and in 1811 became professor of surgery in Berlin. During the war with Napoleon he superin- tended the military hospitals, and after the restoration of peace (1815) he became a mem- ber of the medical staff of the army. Students from all parts of the world attended his lec- tures, and on his visit to England he was the guest of the king. In Paris Dupuytren invited him to take his place as a lecturer. In 1840 he was summoned to Hanover to operate upon the eyes of the crown prince (the present ex-king George), but he suddenly died after his arrival there. The revival of the rhino- plastic process was due in a great measure to the labors of Griife, who propounded his system in his work Rhinoplastik (Berlin, 1818). II. Albreeht von, a German oculist, son of the preceding, born in Berlin in May, 1828, died there, July 18, 1870. He studied mathematics and the natural sciences, and afterward medi- cine, at Berlin, Prague, Vienna, and Paris, devo- ting himself particularly to ophthalmology, and founded in Berlin a private establishment for the treatment of the eyes. He was also pro- fessor of ophthalmology in the university. He was distinguished for great practical and scien- tific acquirements in ophthalmology, the lead- ing journal of this department of medicine at Berlin, Von Grafts Archivfur OpJithalmologim being conducted under his name with the col- laboration of Profs. F. Arlt, F. C. Donders, and Th. Leber. Most of Von Grafe's important contributions were published in this journal. These were papers on the "Physiology and Pathology of the Oblique Muscles of the Eye- ball," on " Double Vision after Operations for Strabismus," on "Diphtheritic Conjunctivitis," on the " Effect of the most refrangible Solar Rays upon Sensation," on the "Treatment of Glaucoma by Iridectomy," on the " Cerebral Causes of Blindness," and on a modified form of the operation for the extraction of cataract. He was also a frequent contributor to the medical society of Berlin and to various medical jour- nals. III. Alfred Karl, nephew and some time assistant of the preceding, born Nov. 23, 1830. In 1858 he graduated at Halle, afterward be- came professor there, and founded an ophthal- mic institute, which is visited by several thou- sand patients annually. He was the first to obtain a recognition of the study of diseases of the eyes as a special science in the Prussian universities. He has published KliniscJie Ana- lyse der Motilitdtestdrungen des Aiiges (Berlin, 1858), Symptomenlehre der Augenmuslfellah- mungen (1867), and Ein Wort zur Erinne- rung an Albrecht von Grafe (1870). GRAFEXBERG. See PRIESSNITZ. GRAFTING, the process in horticulture by which a portion of a plant is made to unite with another plant, whether of the same kind or of another variety or species. The plant upon which the operation is performed is called the stock ; the portion inserted in or joined
