Clarissimo Viro Domino Henrico Oldenburgio, Illustrissimæ Soc. Regiæ Secr. Salutem & observantiam Christianus Adolphus Balduinus.

—QUanquamQuanquam elapso proximè anno officiosissimè scriptas tuas literas testari continuò debuissem quanti facerem, religioni tamen duxi id facere, antequam Phosphorum meum modis omnibus absolutum darem conficerémeque: Quod cùm non multò ante præstiterim, ecce Tibi eundem in theca argentea inaurata; quem, ceu munus exiguum, si fas sit petere à Te, humillimâ subjectione deferre velis cum ipsi Regiæ Majestati tanquam Fundatori & Patrono Societatis Vestræ, imprimis; tum verò Ejusdem Præsidi Illustrissimo, cæterisque Assessoribus & Collegis gravissimis; nihilque intermittere velis, quodcunque vel Clementiæ Regiæ, vel Favori tantorum Virorum conciliando facere arbitreris. Latet in Phosphoro isto ignis & luminis Naturæ realis scintillula, imò secretissima anima, proidéque intrinsecus atque invisibilis Sophorum ignis, visibilem Solis ignem magneticâ ratione attrahens, splendorémque ipsius vicissim in Tenebris emittens ejaculansque. Quo istud accedit non minùs mirum, Signaturam nempe Solis contineri in Universali isto Magnete unde confectus idem ille Phosphorus est; quod quidem ex adjuncto Schemate Phænomeni * * Hoc phænomenon repræsentat in vase vitreo complures imagines Solis, majores, minores; in quas materia, ab Authore nostro adhibita, jucundissimo, ut videtur, spectaculo, abiisse conspecta fuit.(per dies aliquot durante) liquidissimè patet. (789) Atque inde non est, quod subjecto isto uti desistam in Chymicis meis laboribus continuandis, quòd multò majora mihi propediem dignioráque ex se spondeat, quorumque magis arcana ratio. De quibus omnibus, philosophicâ consuetudine, Societati Illustrissimæ relaturus per literas sum quæcunque certis Experimentis comperero. Servet te Deus, & me porrò affectu tuo complectere.

Scrib. Haynæ, d. 1. Sept. 1676.

An Account of four sorts of factitious Shining Substances, communicated to the Publisher from very good hands, both in printed Papers and in Letters not printed.

TWoTwo of these four substances have been already spoken of in two of the late Transactions, vid. Numb. 131. p. 788. and Numb. 134. p. 842; and they are, one of them, the Factitious Paste of Dr. Balduin, shining in the dark like a glowing Coal, after it hath been a while exposed to the Day or Candle-light; the other, the Bononian Stone calcin’d, which imbibes light from the Sun-beams, and so renders it again in the dark, whereas the former needs no Shining Sun, but doth the effect in quite overcast weather and even in a misty day. To these we shall now add two other sorts. The one is by the Germans called Phosphorus Smaragdinus, said to be of this nature, that it collects its light not so much from the Sun-beams, or the illuminated Air, as from the Fire it self; seeing that, if some of it be laid upon a Silver or Copper-plate, under which are put some live coals, or a lighted Taper, it will presently shine, and if the same matter be shaped into Letters, one is able to read it, the other is called Phosphorus Fulgurans, which is a matter, made both in a liquid and dry form, and not only shineth in the dark, and communicates a sudden light to such bodies as 'tis rubbed on; but, being included in a Glass-vessel well closed, doth now and then fulgurate, and sometimes also raise it self as 'twere into waves of light: Differing very much from the Balduinian Stone, which is to be exposed to some shining Body, as the Day, the Sun, the Fire or some lighted Candle, to receive light from thence; whereas this Fulgurating substance carries its light alwaies with it, and when put in a dark place, presently shews the same. Of which we have this further assurance given us, that a little portion of it, having been kept two whole years, hath not yet lost its power of shining: So that 'tis believed, if a considerably big piece were prepared of it, it would serve for a perpetual, or, at least, a very long lasting light.

So far this communication; the effect of which 'tis hoped will in due time appear here amongst us, if the author be competently encouraged thereunto.