REFERENCES.--Dalibard, “Histoire Abrégée,” p. 33; _Dantzig Memoirs_, Vol. I. pp. 407, 409, 411; Johann Gottlob Kruger, “Dissert. de Elect.,” Helmstadt, 1756 (Poggendorff, I. p. 1323); Priestley, 1777, “The Hist. and Pres. State of Electricity,” pp. 82–84; Opuscoli Scelti, 4to, xviii, 55; Pierre Massuet, “Essais,” Leide, 1751; Musschenbroek’s “Epitome elementorum,” etc., 1726, “Tentamina Experimentorum Naturalium,” 1731, and his “Disertatio Physica experimentalis de Magnete,” as well as his “Elementa Physicæ,” 1734, and the “Introductio ad Philosophiam Naturalem,” 1762, the last-named two works being greatly amplified editions of the “Epitome.” For Musschenbroek--Musschenbrock--consult also _Phil. Trans._, Vol. XXXII. p. 370; Vol. XXXVII. pp. 357, 408, also the following abridgments: Baddam, 1745, Vol. VIII. p. 42; Reid and Gray, Vol. VI. p. 161 (Musschenbroek to Desaguliers); Hutton, Vol. VII. pp. 105, 647 (magnetic sand); Eames and Martyn, Vol. VI. part ii. p. 255; John Martyn, Vol. VIII. p. 737 (magnetic sand). For this magnetic sand, consult also Mr. Butterfield’s article in _Phil. Trans._ for 1698, p. 336 and in the abridgments of Hutton, Vol. IV. p. 310. =A.D. 1745.=--Watson (William), M.D., F.R.S., an eminent English scientist, bears “the most distinguished name in this period of the history of electricity.” His first letters, treating of this science, are addressed to the Royal Society between March 28 and October 24, 1745, and, on the 6th of February and the 30th of October, 1746, he communicated other similar papers to the same Society, all which, like his subsequent treatises, are to be found in the _Philosophical Transactions_. Dr. Watson, like most scientists at the time, made numerous experiments with the Leyden jar, and he was the first to observe the flash of light attending its discharge. He says: “When the phial is well electrified, and you apply your hand thereto, you see the fire flash from the outside of the glass wherever you touch it, and it crackles in your hand.” It is to him that we owe the double coating of the jar, as well as the _plus_ and _minus_ of electricity. He also shows conclusively that glass globes and tubes do not possess in themselves the electrical power, but only serve “as the first movers or determiners of that power,” and he also proves that the electric fluid takes the shortest course, passing through the substance of the best medium of connection and not along its surface. This, he demonstrated by discharging a phial through a wire covered with a mixture of wax and resin.