From 1822 to 1827 inclusively, 52 puds[41] and 22-1/2 pounds.
1828 94
1829 78 31-1/2
1830 105 1
1831 to 1833 348 15
[41] One pud = 40 Russian pounds, = 69,956 Prussian marcs (see
SILVER); 1 pound = 96 zolotniki.
ANALYSES of the PLATINUM ORES of the Urals, and of that from Barbacoas
on the Pacific, between the 2nd and 6th degrees of northern latitude.
+------------+---------------------+-------------+----------+
| |From Nischne-Tagilsk.| | |
| | Berzelius. |Goroblagodat.|Barbacoas.|
| | | Not | Osann. |Berzelius.|
| | Magnetic.| Magnetic | | |
+------------+----------+----------+-------------+----------+
|Platinum | 73·58 | 78·94 |83·07 | 86·50| 84·30 |
|Iridium | 2·35 | 4·97 | 1·91 | | 1·46 |
|Rhodium | 1·15 | 0·86 | 0·59 | 1·15| 3·46 |
|Palladium | 0·30 | 0·28 | 0·26 | 1·10| 1·06 |
|Iron | 12·98 | 11·04 |10·79 | 8·32| 5·31 |
|Copper | 5·20 | 0·70 | 1·30 | 0·45| 0·74 |
|Undissolved}| | | | | |
|Osmium and }| 2·30 | 1·96 | 1·80 | 1·40| |
|Iridium }| | | | | |
|Osmium | | | | | 1·03 |
|Quartz | | | | | 0·60 |
|Lime | | | | | 0·12 |
| +----------+----------+------+------+----------+
| | 97·86 | 98·75 |99·72 | 98·92| 98·08 |
+------------+----------+----------+------+------+----------+
PLUMBAGO. See GRAPHITE, for its mineralogical and chemical characters.
The mountain at Borrowdale, in which the blacklead is mined, is 2000
feet high, and the entrance to the mine is 1000 feet below its summit.
This valuable mineral became so common a subject of robbery about a
century ago, as to have enriched, it was said, a great many persons
living in the neighbourhood. Even the guard stationed over it by the
proprietors was of little avail against men infuriated with the love of
plunder; since in those days a body of miners broke into the mine by
main force, and held possession of it for a considerable time.
The treasure is now protected by a strong building, consisting of four
rooms upon the ground floor; and immediately under one of them is the
opening, secured by a trap-door, through which alone workmen can enter
the interior of the mountain. In this apartment, called the
dressing-room, the miners change their ordinary clothes for their
working dress, as they come in, and after their six hours’ post or
journey, they again change their dress, under the superintendence of the
steward, before they are suffered to go out. In the innermost of the
four rooms, two men are seated at a large table, sorting and dressing
the plumbago, who are locked in while at work, and watched by the
steward from an adjoining room, who is armed with two loaded
blunderbusses. Such formidable apparatus of security is deemed requisite
to check the pilfering spirit of the Cumberland mountaineers.
The cleansed blacklead is packed up into strong casks, which hold 1 cwt.
each. These are all despatched to the warehouse of the proprietors in
London, where the blacklead is sold monthly by auction, at a price of
from 35_s._ to 45_s._ a pound.
In some years, the net produce of the _six weeks’_ annual working of the
mine has, it is said, amounted to 30,000_l._ or 40,000_l._
PLUSH (_Panne_, _Peluche_, Fr.; _Wollsammet_, _Plüsch_, Germ.), is a
textile fabric, having a sort of velvet nap or shag upon one side. It is
composed regularly of a woof of a single woollen thread, and a two-fold
warp, the one, wool of two threads twisted, the other, goat’s or camel’s
hair. There are also several sorts of plush made entirely of worsted. It
is manufactured, like velvet, in a loom with three treadles; two of
which separate and depress the woollen warp, and the third raises the
hair-warp, whereupon the weaver, throwing the shuttle, passes the woof
between the woollen and hair warp; afterwards, laying a brass broach or
needle under that of the hair, he cuts it with a knife (see FUSTIAN)
destined for that use, running its fine slender point along in the
hollow of the guide-broach, to the end of a piece extended upon a table.
Thus the surface of the plush receives its velvety appearance. This
stuff is also made of cotton and silk.
POINT NET, is a style of lace formerly much in vogue, but now superseded
by the bobbin-net manufacture.
PORCELAIN, is the finest kind of pottery-ware. It is considered under
that title.
PORPHYRY, is a compound mineral or rock, composed essentially of a base
of hornstone, interspersed with crystals of felspar. It frequently
contains also quartz, mica, and hornblende. That most esteemed is the
antient porphyry of Egypt, with a ground of a fine red colour passing
into purple, having snow-white crystals of felspar imbedded in it. Most
beautiful specimens of it are to be seen in the antique colossal statues
in the British Museum.
Porphyry occurs in Arran, and in Perthshire between Dalnacardoch and
Tummel bridge. It is much used for making slabs, mullers, and mortars.
PORTER, is a malt liquor, so called from being the favourite beverage of
the porters and workpeople of the metropolis and other large towns of
the British empire; it is characterized by its dark-brown colour, its
transparency, its moderately bitter taste, and peculiar aromatic
flavour, which, along with its tonic and intoxicating qualities, make it
be keenly relished by thirsty palates accustomed to its use. At first
the essential distinction of porter arose from its wort being made with
highly-kilned brown malt, while other kinds of beer and ale were brewed
from a paler article; but of late years, the taste of the public having
run in favour of sweeter and lighter beverages, the actual porter is
brewed with a less proportion of brown malt, is less strongly hopped,
and not allowed to get hard by long keeping in huge ripening tuns. Some
brewers colour the porter with burnt sugar; but in general the most
respectable concentrate a quantity of their first and best wort to an
extract, in an iron pan, and burn this into a _colouring_ stuff, whereby
they can lay claim to the merit of using nothing in their manufacture
but malt and hops. The singular flavour of good London porter seems to
proceed, in a great degree, from that of the old casks and fermenting
tuns in which it is prepared. Though not much addicted to vinous
potations of any kind, I feel warranted by long experience to opine,
that the porter brewed by the eminent London houses, when drunk in
moderation, is a far wholesomer beverage for the people than the thin
acidulous wines of France and Germany. See BEER.
PORTLAND STONE, is a fine compact oolite, so named from the island where
it is quarried. It is a convenient but not a durable building-stone.
POTATO (_Pomme de terre_, Fr.; _Kartoffel_, Germ.); is the well-known
root of the _Solanum tuberosum_.