OCH 
e 
Chinefe become the purchafers. Peroufe’s Voyage, vol. ii. 
appendi 
POCHOTSK, or OxuotsK, Mountains, a great chain, 
known under the name of Stanovoi-Krebet, which borders 
upon the Nertfhinfkoi, or upon the Yab blonoi-Krebet, near 
the region of the fources of the Aldan and Oldekon, runs 
thence on one fide northward on the Lena down to Yakutfk, 
and ha the other fide weftward to the Oudinfkoi gulf of the 
Okhorfkoi fea, which fwarms with iflands ; proceeds round 
this to the Upper Okhozfk, and ftrikes out "feve ral branches 
promontory 
daa pase of Keariea All thefe extenfive mountains 
e almoft entirely unknown. From the diftri& of Okhotfk 
tae been brought jafper, porphyry, and beautiful chalce- 
donies and carneoles, {ulphur-pyrites, ~ alum, agaricus 
aluminaris, mountain cryftal, coals, &c.; and here are like- 
The mountain is, for the moft part, not 
Its Saar rivers on the Ruffian 
he Amga, Idan, the Uda, the 
aia, the Yana, ‘the “Tadiphicka, the Kolyma, and the 
na 
OCHOT TSKOE, or Oxnotsxo1, Sea, a large bay of 
the North Pacific ocean, on the E. coaft of the Ruffian do- 
minions, fo called from the fea-port of — or Okhotfk. 
Bees E. long. 137° to 
OCHR 
CHRE, in the ris, a yellow a. of an earthy ap- 
It in n general confifts of fom ote as lime or 
r 
o fulphuret of iron. This falt, by expo 
to the oxygen of the atmofphere, ca refolves bees int 
two falts, namely, the fuper-oxyfulphat of ir 
fub-oxyfulphat. The latter, being info pees is neces 
forming a yellow depofit, frequently feen in fuch chaly- 
beate fprings as refult from the a sapohen of pynites 
“his yellow precipitate’ penetrates the earth and tinges it 
with the fame colour, but more dilute. The mixture con- 
ftitutes a fpecies of ochre. When the foil, with which the 
fubfalt combines, confifts of certain proportions of lime and 
alumine, free from nia or other heterogeneous matter, the 
ochre 1s more yalua 
Thofe aphs ate which contain the fuper-carbonat 
of iron, = which are frequently found, are capable o 
forming o different quality from the laft. 
The eahanee a in the water is fuper-carbonat with the 
black oxyd of iro 
OCH 
form of an infoluble powder of a yellow colour. This ochre 
is of a deeper yellow than that derived from the fub-oxyful- 
at. Its colour may be converted into a beautiful brown 
by applying a heat to it, fufficient to expel its carbonic acid, 
he fecond oxyd of iron. The heat of boil- 
water is fufficient for this purpofe. his ochre, fo 
changed, has ° roperties of umber. The 
ong expofure to the air. "As pe remains in this rae it 
will gradually refolve itfelf into the fuper-oxy{ulphat and the 
fub-oxyfulphat ee latter falls to the bottom of the veffel 
in the form of a We pee which, when wafhed ane 
dried, puaaane a bent coiou 
When carbonat of potath is added to the fuper-oxyfulphat, 
the pe of iron will be formed, which will precipitate 
in the ftate ofa yellow powder. This powder, when wafhed, 
ihe foil, which is the pafture of the roots, contraGtin 
mouths “of the fibres, contaminating the juices, and 
operating to the enki of the tree, by poifoning it, wand 
haftening i its diffolutio 
It is well known citer ochres alfo form the bafis of various 
kinds of pigments, paints, and other fimilar matters 
O Willd. Princip. of Bot 
ame given by Ro 
ied enfolds the flower-ftalks in Cyperus, and fome fimilar 
plants, in the form of a clofe membranous fheat “here 
feems little occafion for this term, nor is it advitable to give 
into the too general practice of botanilts, who, in writing 
upon any one particular tribe or natural order, invent new 
terms without neceffity. The terms braéea, involucrum, 
ceptacley &c. are univerfal, and we fhould be involved in 
great confufion if we had a feparate name for in every 
different natura he cryptogamic authors are moft 
pron this inconvenient cuftom, becaufe they fancy the 
plants with = = they are converfant muft, in every thing, 
differ from 
OCHROITE of Klaproth, in eee is the Cerium 
of the two Swedifh chemifts, Hifenger and Berzelius, and 
the ee aH Tunesten of Scheele ; hich fee. 
ROMA, in Botany, fo named by Profeffor Swartz, 
from ies s, pale, in allufion to the pallid hue of its flowers, 
faves, and wool of its feeds. Swartz Prodr. 97. a rae 
_Schreb. ASS: illd. Sp. Pl. v. 
—Clafs and order, ° Monadelphin Pow 
“ Juff. 
h 
lanceolate, falling leaves ; inner of one leaf, Roel. -fhaped, 
ve-cleft. Cor. Petals five, wedge-flaped, coriaceous. 
Stam. 
