often refer to these acta, as the most authentic.

sources.

EAU DE LUCE.

THE article sold under this name by perfumers, when properly and well made, is a fluid volatile soap, of a pale white or milky colour, with an exceedingly strong and pleasant smell, which, instead of fixed alkali and tallow or fat oil, the component parts of common soap, consists of caustic volatile alkali and highly purified oil of amber. When of the best quality, it always retains its milky colour; but this is not the case when spirit of sal ammoniac and oil of amber are mixed together. The making of this article requires operations which were long an object of research to chemists, who have given different recipes for preparing it, each said to be superior to the other. Some assert that this liquid can be made per

* The best account of these acta publica, together with the ne cessary proofs, may be found in Lipsii excursus A ad lib. V. Annal. Taciti, in Taciti Opera, edit. Lipsii. Antverpiæ 1627, fol. p. 5265; or in Taciti Opera, edit. Burmanni. Trajecti 1721, 2 vol. 4to. i. p. 743. Also in Maternus de Cilano Römischen Allerthümern, i. p. 401. The latter remarks, that Lipsius has admitted, without any proof, that these acta were ordered to be published even by Servius Tullius, king of Rome. He thinks he found some articles from these Roman news-papers in Th. Reinesii Syntagma Inscriptionum, p. 140, which he has inserted.

fectly pure and bright without any prejudice to its quality.

As a soap, it is employed to remove from cloth many spots which cannot be removed by common soap; and it is the fitter for this purpose as it very speedily evaporates. Mixed with water it is administered also for various diseases and accidents; such, for example, as the bite of some snakes; and in consequence of its strong smell, it acts, when held to the nostrils, as a powerful stimulant in cases of fainting. But it is requisite that those who use it for the latter purpose should know, that a sinall drop of it, if it came in contact with the eye, would occasion blindness.* This caution ought to be affixed to each bottle in which it is. sold.

That this Eau de Luce, was first made known towards the middle of the last century, appears to be certain. In the writings of Neumann, Hoffmann, Boerhaave,† and other cotemporary writers,

Some melancholy instances of this are given in the Gazette salutaire; but in that work, which has no index, I have not been able to find them.

+ See Boerhaave elementa chemiæ, Lugd. Bat. 1732. 4to. ii. p. 370. and Fr. Hoffmanni observat. physico-chymic. lib. ii. obs. 11, which in Gesner's edition of his works stand in vol. iv. p. 492. Where he speaks of the spirit of sal ammoniac prepared with lime,' he says: Externe in affectibus soporosis, apoplexia, ad excitandum non sine insigni commodo naribus applicari potest, et quia cum spiritu vini rectificatissimo amice jungitur, quod non fit cum spiritu sa Es ammoniaci, ex cineribus clavellatis vel sale alcali et sale ammo

I do not find any mention of it, though they treat of similar mixtures, alcali volatile oleosum, and the so called offa Helmontii. In the year 1741, when Geoffroy's Materia medica was printed, it must not have been very common; for the author, where he speaks of all the preparations of amber, takes no notice of it; and yet it is known, that this chemist afterwards gave himself a great deal of trouble to discover the method of preparing it. In the continuation of that work, which was not written by Geoffroy, it is mentioned. Dumachy said, in 1756, that Eau de Luce had been known at most half a century. The Chevalier de la Chapelle, which however is a fictitious name, says that he had a bottle of this water inade in 1742; and this is the earliest mention of it with which I am acquainted.§

The name of the inventor also I cannot state with certainty. It seems to be denoted by the appellation de Luce; but this is explained so many ways, that nothing can at last be deduced from it.

niaco parato, maxime inservit ad extemporaneam salis volatilis oleosi, secundum Sylvii methodum, præparationem.

It is generally believed that this soap was first made known by von Helmont, in his book de lithias, c. 7. § 5. under the barbarous name of Duelech; but it was before described by Raymond Lullius, Exper. 7 and 8.

↑ According to the German translation, i. p. 248. and vii. p. 52.

Recueil periodique d'observations de médecine par Vandermonde, tom. iv. an. 1756. p. 460.

§ Ibid. tom. v. an. 1756. p. 224.

Some translate it Aqua Luccana,* others Aqua St, Lucia;† some Aqua Lucii, and some also write it Eau de Lusse. Many, however, are of opinion that an apothecary at Lisle in Flanders, or at Amsterdam, named Luce, was the inventor. This is said also by Malouin, the new editor of Lemery's chemistry, | Lier and others. ||

On the other hand, most of the French writers assert that this water was first made at Paris; and for a long time by one apothecary only, named Dubalen, who, as well as his successor Juliot, carefully kept the process a secret.** Others afterwards endeavoured to imitate it, and among these, was the apothecary Luce at Lisle, who however gave to the water a blue colour, because he was not able to make it of a milky appearance. The

• Wallerius physische Chemie, ii. p. 348.

+ Gmelin apparatus medicaminum. Regnum miner. i. p. 101. Stockar de Neuforn diss. de succino. Lugd. Bat. 1760. p. 65. § Medicin. chemie, i. p. 146, and ii. p. 307.

Cours de chymie par Lemery. The new edition, enlarged by Baron. Paris 1756. 4to. p. 517.

¶ Verhandeling over de slangen en adders door I van Lier. Amst. 1781. 4to. p. 177. On nomme ce melange Eau de Luce, vraisemblablement d'après un certain Lucas, Apoticaire á l'Isle, qui s'est fait un nom par la preparation d'une pareille liqueur penetrante. I have mentioned this book in Physikal ækon. Biblioth. xii. P. 450. Demachy says, in L'art du distillateur d'eaux fortes, p. 126: L'état constamment laiteux lui a fait donner le nom d'Eau de Luce. This derivation I do not understand.

** See the before quoted collection of Vandermonde, v. p. 237, 239, 307, 308.

novelty of this blue water, which had its colour from copper, procured it great approbation; so that the blue Eau de Luce banished, for a long time, the genuine kind.*

I have given this account, though uncertain and defective, that others may have an opportunity of correcting or enlarging it; which, as the invention is so modern, there is reason to hope may be done. I shall remark also, that Dossie, an Englishman, is among the first who gave a proper account of the preparation of this water, namely in his Elaboratory laid open, printed in 1758.

SUGAR OF MILK.

SUGAR of milk is an essential salt, obtained from milk by evaporation and crystallisation. It differs in its nature, according to the method of preparation; and by repeated purification it becomes always less saccharine, as common sugar by being refined loses some of its sweetness, although the contrary in general is believed. The invention

* In Dictionnaire des origines, iv. p. 313, is the following article: Eau de Luce. Cette liqueur laiteuse, volatile, tres-pénétrante, formée par la combinaison de l'esprit volatil de sel ammoniac, avec une petite portion d'huile de karabé, fut inventée par M. du Balen, apothecaire de Paris. On ne doit point la confondre avec un autre eau volatile de couleur bleue qui eut beaucoup de vogue sou le nom du Sieur Luce, apothecaire á Lille.