still to be seen. Major-general von Trew and Mr. Owenus had the goodness to show me those still preserved in the arsenal at Hanover. Those which I consider as the oldest, had on the barrel the figure of a hen with a musket in its mouth, because perhaps they were made at Henneberg. A pistol of this kind was entirely of brass without any part of wood, and therefore exceedingly heavy. On the lower part of the handle were the letters J. H. Z. s. perhaps John duke of Saxony. A piece with a wheel, which seemed to be one of the most modern, had on the barrel the date 1606. Together with fire-stones, properly so called, pyrites, which is sometimes named fire-stone, continued long in use. In the year 1586, under duke Julius of Brunswick, when abundance of sulphureous pyrites was found near Seefen, the duke caused it to be collected and formed it himself into the necessary shape, though in doing so he often bruised his fingers, and was advised by the physicians not to expose himself to the sulphureous vapour emitted by that substance.* G. E. * Rehtmeiers Braunschw. Lüneburg. Chronica, p. 1070. Damit nichts zu spilde sondern alles zu Nutz käme, liess er solche Nieren und Steine alle Tage durch die Edel-Knaben und Trabanten herein holen und schlug die selber klein, etzliche Tönnichen voll und zog den Schwefel ins Gehirn, dass ohn Zweifel derselbe, vorerzählter Maassen, die weisse phlegmatische Materie rege gemacht und zum Fluss gebracht. Er wolte sich aber davon night abreden lassen, ungeachtet er oftmals die Finger entzwey schlug, dass das Blut darnach folgete so er doch nicht achtete. Stahl, in a dissertation published in 1716, mentioned an observation he had made in regard to that pyrites, which, as he says, was then used for fire-locks, under the name of Feuer-Büchsen stone.* SEIGNETTE'S SALT. SAL POLY- THIS neutral salt, which consists of the mineral alkali, soda, and the acid of winestone, was prepared and made known, about the end of the seventeenth century, by a Frenchman named Seignette. The confidence with which he recommended it, and the care he employed to keep the process for making it a secret, produced, as in general, so much effect, that it was used in preference to other medicines long known, which had been of no less service; so that the inventor was enabled to acquire a fortune without much trouble. It must, however, be confessed, that he was an expert chemist, who had before gained the Joh. Stretz Dissertat. de vitrioli elogiis, Hala 1716. p. 13: Minera illa sulphureo-martialis, in Variscis fodi solita, e qua pyritæ pro bombardis Germanici ignitabuli formantur vulgo FeuerBüchsen-Steine. esteem of naturalists and physicians by some learned dissertations, and by various medicines which he had invented. Peter Seignette was an apothecary at Rochelle. He wrote an account of some remarkable natural productions in that neighbourhood, in the Transactions of the Academy of Sciences at Paris, or in other works, and died on the 11th of March, 1719.* This salt, by which he acquired celebrity as well as riches, he recommended in some papers printed separately, and particularly in the year 1672. He called it sometimes alkaline salt, sometimes sal polychrest, and sometimes Rochelle salt; and after his death it continued to be sold by his son for a long time, with the best advantage. The mechanics have often been reproached with a want of confidence in the learned; but, in my opinion, the latter give too much cause for it. To the great mortification of human pride it must be confessed, that the most useful inventions occur to the former amidst their continual labours; and their merit consists chiefly in this, that they prosecute the discovery, seize it, and turn it to advantage. If they succeed, their interest requires that they should keep it a secret, in order to gain • In Bibliotheque historique de la France par Le Long, augmentée par Fevret de Fontelte, Paris 1778. 5 vol. fol some of Seignette's writings are quoted; such, for example, as a paper in Memoirs de l'Acad. 1707. p. 115, also in Histoire de la Rochelle, par M. Arcére, ii. P. 424. by a monopoly. No sooner has the literary man heard of a new art, than he wishes to become the second discoverer; and with the greater anxiety the more important the invention is, and the more it has been concealed. If he discovers it, he hastens to communicate it to the public; because, in general, he gains only by making his exertions known. The man of letters, therefore, has a great advantage over the mechanic. He acquires the character of a patriot and friend to mankind, who endeavoured to render the important advantage public; and his exertions being more applauded, he is thus enabled to throw a shade over the merit of the mechanic. These contending interests, however, are of great advantage to the whole society of which both parties are members, I mean to the public good. When the mechanic invents any thing new, the man of letters diffuses a knowledge of it, and makes it generally useful; takes care that no injury arises from it by a monopoly; that it does not die with the inventor; and, by examining the causes and defining the laws of the invention, he renders the application of it more certain, and shows how it may be employed for purposes of which the inventor never perhaps entertained an idea.* If in this manner he lessens • Nam invenire præclare, enuntiare magnifice, interdum etiam barbari solent; disponere apte, figurare varie, nisi eruditis, negatum est. Plin. epist. iii. 13. the merit of one, he, on the other hand, creates employment to many, and gives rise to researches in which thousands participate with advantage. In this manner, Seignette the apothecary discovered sal polychrest, while engaged in making soluble tartar. Having employed salt of soda instead of winestone, under the old idea that there was only one kind of fixed alkali, he unexpectedly saw produced a salt different from the common soluble tartar which he wished to make, and from every other known saline substance. On examination he found it to be a new laxative, recommended it as such, and by the sale of it acquired a fortune. Scientific men examined this secret salt; found out the component parts of it; made them publicly known; and caused the difference between the mineral and vegetable alkalies, before overlooked, to be more accurately examined,* by which means much light was thrown on chemistry, and many of the arts were improved. Among those who contributed to bring the new salt into vogue was Nicholas Lemery who received a large quantity of it from Seignette, and distributed it at Paris, but without making known its Who first discovered the difference between the vegetable and mineral alkali? To this qtion professor Gmelin returned the following answer: That, a by Stahl. See G. E. S experimentalis. Norim 304. rate, it had been accurately defined menta chymia dogmatica et vol. 4to. iii. p. 268 and |