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[ On the different sorts of oils and bitumens, see Dr. Watson’s (the present bishop of Llandaff’s) Chemical Essays, vol. iii. essay i., a classic book, the best adapted to infuse the taste and knowledge of chemistry. The less perfect ideas of the ancients may be found in Strabo (Geograph. l. xvi. p. 1078) and Pliny, (Hist. Natur. ii. 108, 109.) Huic (Naphthae) magna cognatio est ignium, transiliuntque protinus in eam undecunque visam. Of our travellers I am best pleased with Otter, (tom. i. p. 153, 158.)]
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[ Anna Comnena has partly drawn aside the curtain. (Alexiad. l. xiii. p. 383.) Elsewhere (l. xi. p. 336) she mentions the property of burning. Leo, in the xixth chapter of his Tactics, (Opera Meursii, tom. vi. p. 843, edit. Lami, Florent. 1745,) speaks of the new invention. These are genuine and Imperial testimonies.]
21 ([return])
[ Constantin. Porphyrogenit. de Administrat. Imperii, c. xiii. p. 64, 65.]
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[ Histoire de St. Louis, p. 39. Paris, 1668, p. 44. Paris, de l’Imprimerie Royale, 1761. The former of these editions is precious for the observations of Ducange; the latter for the pure and original text of Joinville. We must have recourse to that text to discover, that the feu Gregeois was shot with a pile or javelin, from an engine that acted like a sling.]
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[ The vanity, or envy, of shaking the established property of Fame, has tempted some moderns to carry gunpowder above the xivth, (see Sir William Temple, Dutens, &c.,) and the Greek fire above the viith century, (see the Saluste du President des Brosses, tom. ii. p. 381.) But their evidence, which precedes the vulgar aera of the invention, is seldom clear or satisfactory, and subsequent writers may be suspected of fraud or credulity. In the earliest sieges, some combustibles of oil and sulphur have been used, and the Greek fire has some affinities with gunpowder both in its nature and effects: for the antiquity of the first, a passage of Procopius, (de Bell. Goth. l. iv. c. 11,) for that of the second, some facts in the Arabic history of Spain, (A.D. 1249, 1312, 1332. Bibliot. Arab. Hisp. tom. ii. p. 6, 7, 8,) are the most difficult to elude.]