GAR. 
at-Edinburgh, beri he. took. the degree of M.D. in 1788. 
e thence repaired to London, and purfued his profeffional 
He fettled as 
, and 
arrowgate his reputation greatly i in- 
creafed, and re ref slved to Tt his refidence for a field fill 
with which he complied, and gave great and general 
faCtion, and his fame Ipread around, infor ich hai he was 
afterwards induced to rep anchefter, War- 
rington, an icalt te was a invited to leGture at 
Birm: ngham and Dublin when he was -informed of the va- 
cancy at Anderfon’s Tai oa at Glafgow, the ida 
fhip of which was handfo omely offered to him, and he be 
his leGtures there in Nov. 17 
his tour to the Highlands, an _aceount 
i At the = Ro 
» Dr. Gar was ted by co 
Rumford to become the iene: ‘he eae the pe 
pointment, and the lecture -room was saniaee _ ari 
of the firft diftin@ion and fa of his 
arrival in London, however, he dea ‘his ee to the 
moft 
anand of his profeffion, as likely to afford the per- 
ent means of cera 3 but his plans and profpe were 
ath on she 28t 
‘il ens ated by of June, 
ofthumous volume, ae « Zognomia,”? was pu ublithea for 
the inte ofhis oe bag Se} the preface to thatwork. 
tneralogy, a fpedies pcg oe as fubor 
die to the filiceous oan - foffily. e fubftances that 
compofe it exhibit a remarkable fimilarity of aS bhi 
ur, a 
have been. aeeidest a + new 
ies. Haity, cohen) i. the 
“jens = confo weet under the see 
s-f{ubftances defcribed as 
and common garnet, anata, oe lahohee oa: 
zolete, fuccinite, and melanite. Werner’s divifion of this 
{pecies into the two fub-f{pecies of — and common garnet, 
hough it may not draw a perfeQ- of demarcation be- 
tween the two fubftances, is ftill oe practical utility, and 
nded on chemical and geological obfervation. 
We “hall pr naes the fame divifion, but add lkewife, as fub- 
{pecies, the > pyrope and melanite, both of which, from geog- 
the 
The uniting into one mafs extenfive 
arnet, 
names 
Spica: of his 
name of grengi. 
Wernerian fyftem. 
fuites of fubitance pearance and compofition 
merely becaufe we difcover the fame type yftallization 
in n great inconvenience: to 
in dete 
fois. leeeal sary er the follows, fub-ipecies may 
hereafter occupy in the fyftem. The chemical diftinGion 
“afforded by the preience of a greater proportion of lime in 
4 
a 
cording to cir eee 
GAR 
the common garnet and the magnefia as a eae part-of 
the pyrope-garnet, though it may affift in, is ftill much too 
vague entirely to a ati the diftribution of oe granatine 
arnet.—Almandine, a 
7 Fe, 
on one fide into 
e blue often osafideratiy pr edits on on the other 
into hyacinth-red and reddifh ye 
It is fometimes found maffiv cy ‘ai fleminated, but gene- 
rally cryftallized. The principal modifications of the cryftals 
5 
. The rhomboidal Reaimecey alfo denominated the. 
part oieceicion, is 
mitive form. 
foc a three ples . each end ase their hom 
boidal form, be confidered as acuminating aes 
fet on the fea Lead edges of the prifm. (Grenat 
a alongé, Haiiy, 
. The primitive cryftal having ak edge intercepted 
ve a fingle plane. This se as 36 planes, 12 of 
which are ae ha 24 hexagons. (Grenat emarginé, 
Haiiy, pl. 46. fig. 57. i forms the tranfition into 
. The leuci or roundifh cryftal with 
twenty-four seit nal dal eae ; which is defcribed alfo 
as a low, double, sabe ae pyramid, wit th the lateral planes 
the one fet on the Jateral planes of the other, and hav- 
ae each fummit acuminated by four planes fet on the alter- 
nate lateral edges. (Grenat era Haiiy, pl. 46. fig. 
56. 
What is defcribed as leucite cryftal, in which the angles 
formed by the os of the different trapezoidal planes 
are truncated, is a ariety of modif. N*°2.in which the 
rhombs are mu ule than the hexagons. 
_ 4. The ag dodecahedron as each = its edges in- 
tercepted by three planes, or modif. N~ 2, increafed b 
- planes betwee ‘the rhom aut feadoae (ma trié~ 
arginé, Haity, pl. 46. fig. 58. 
— Modific. oy 2, aac eahcaee by 24 til all the 
He, formed by the ing of four hexagons being 
nt cepted each ie a narrow plane. (Grenat uniternaire, 
Haiiy, pl. ae fig. 59.) 
: e d a capeenlee belong to the noble 
garnet ; they nites ur, ee e rarely, in = 
aa ‘and at featt, No I ahd 2, in ae e melanite garn 
The cryftals are found of all Bees, Ha that of the head of 
in to that of a clenche » and upwards ; the 
latter ege a always to this a ec and yada to 
Mod. N° 1. and its elongated va They und im 
bedded or loofe, not in ao. "Their furface i is generally 
mooth, but not feldom furnifhed with ftrie or furrows in- 
rece of fa rane of the lamine on the rhomboidal 
primitive pla 
hile th £41 Ray } 
that of the interior is peer eere 
more or lefs {plendent 5 it is between vitreous and re 
finous. 
nerd Lia is generally perfectly. éonchotdel, approaching 
fometimes to uneven and fplintery ; and in fome cafes it has 
ban “bfeved to border on fo Tea ed. Fragments indeter- 
minately cake. more a we Seue! oa Seay laos the maffive 
rway, is generally com- 
noble pee) efpeciall ee 
Seria pra Soles, ti 
de 
pofed of fine or coar. 
