B O O K « it ihould exift in a lefs proportion than the fluid part.
“ To inftance in magnefia, gypium, and atom, in all which
“ the genus is determined from the fol-id ingredient, or the
“ earth, and not by the fluid part or vitriolick acid, al-
“ though the quantity o f the latter greatly exceeds that of
“ the former.
“ The fpecifick characters are to be deduced from the dif-
“ ferent combinations and proportions o f the feveral princi-
fg pies in each.
“ All mineral bodies fall into four great clafles : I. Salts;
g II. Earths'; III. Bitumens ; and,IV. Metals.
“ G l a s s I. S a l t s .
“ Salts are acid, alkaline, neutral, earthy, and metallick.
“ In this clafs, to the three well-known acids o f vitriol, nitre,
“ and fea-falt, the author, befide introducing the phofpho-
“ rick acid as a principle, has joined alfo the fluor acid ; the
•if acidof arfenick; one newly difcovered in black-lead,called
“ the acid o f molybdena; one called the acid o f calx ponderofa;
“ the acid o f borax ; that o f amber; -and laftly, the aerial
if acid, or fixed air.
“ The fluor acid, flrft difcovered byMr.Scheele, has, while
“ in the form o f vapours, the power o f corroding glafs, and
“ with water forms filiceous earth *. j It is found united to
“ a calcareous bafe in the fluor mineralis; and, as profeffor
f| Bergman ftrongly fufpe&s, enters into the compolition of
“ all filiceous bodies.
“ The acid o f molybdena the profelfor conjectures to be of
“ metallick origin; and he thinks there is reafon to believe,
“ that each metal has its peculiar acid, although, as yet, from
* I t has been fince difcovered and a c - does h o t, as h e imagined in this p la c e , when
knowledged by th e au th o r , that a lth o u gh in a Hate o f v ap o u r , ac tually form filiceous
th e flu or acid difiolves filiceous ea rths e a r th w ith w a ter ,
whene ve r it meets w ith them ; y e t , that it
“ the
‘ the ftronger union o f the acid with the phlogiiton, it has CHA]>-
‘ ‘ not been developed^ except in arfenick, where the cohefion » V*U'--
V. is lels firm.
“ To the number o f alkaline faits, there is no addition.
“ The neutral are divided into perfeâ and imperfeit r the
“ latter, bc-Ln.g thofe in which one o f the component princi-
“ pies,- exifts, either in a fm aller quantity,, or is weaker in its
“ power than isifmlly requifite. The more pcr-feit neutral faits,
“ formed by the union o f the three alkalies, with the three
“ primitive mineral acids, are well known. The imper-
“ feci anrej. tincal or borax, being the mineral alkali partially
“ impregnated with a. peculiar acid; the vegetable alkali
“ united with the aerial acid; which, he obferves, is
fft feldom found native, except in the neighbourhood o f great
“ woods ddtroyed hy fire ;. the alkali minerais aeratum,
“ or-.matron;. and the alkali- volatile- a'èratum ; for an ac-
“ cfiuntof which fee: Phil. Tranf. Vol. LVII.
I Among the earthy faits he has introduced that from
f which.the i r f t o f his primitive earths, is produced. He
“ .calls-it terra ponder o f a vitricdata'. , Among the faits the
« profeflor has alfo brought the gypfum, or felenites, under
“ the name o f calx. vitriolata-r the calx nitrata, or terrene
“ nitre, found fparinglyr in waters. He relates, upon this
“ article, that there are.-faid to be chalk-liills in France fpon-
“ taneoufly impregnated with the nitrous acid ; the calx fa -
“ lit a, or fixed ammoniacal fait; the calx àèrata, or marble,
“ lime-ftone, &c. o f waters ; the magnefia vitriolata, or Ep-
“ fom fait ; the magnefia nitrata aerata ; and finally, the
“ alum,.or argilla vitriolata.
“ The metallick faits are, the cuprum vitriolatum, or blue
“ vitriol ; ferrum vitriolatum, or green vitriol; ferrum a'era-
“ turn, or iron diflolved by the aerial acid in mineral waters ;
“ Niccolum