The Yale expositor., 1911-09-14

y
ceived the idea of building. The maltha-lined cs-
terms found in Egypt and at Petr@a although of
unknown antiquity, still in q perfect state
OF preservation and fit for practical use. 1t is al
80 wellestablished fact that in the preparation
of material for embalming and encaustic painting
in Egypt and Mexico maltha formed the principal
part.
Many theories have been advanced as to how
bitumen has been produced but general chem
zeal formula can be given for the occurrence Of
the several curious forms of the product There
is no doubt however that bitumen represents
a substance that is obtained from petroleum.
found in its liquid state in the containing rocks,
and by the process of natures laboratory has
been gradually converted into its more solid form.
This process may be described evaporation.
AS the oil seeps to the surface, generally by it's
own gaseous pressure, the natural gases, spir-
!tuous and light oils evaporated by the sun,
and the residues, asphatum and maltha, formed.
Indications Of the presence of petroleum are fire.
Quentfy found on the surface in the form of btu
men, but there is fixed rule, and recent dis
eoveries seem to upset the theory that oil can
only be found under certain conditions Wells
have been sunk and oil found along the coast of
California, where the operations have even ex-
tended for some distance into the In
variety Of climates and from the sea level up
through the lofty ranges of the Andes has this
remarkable Eight of the world" been secured.
Petroleum, also known as mineral OIL crude
OIL, and stone oil, may be described as a liquid
sorm of bitumen, found seeping from the crevices
OF rocks and floating about on the surface of the
water. Its color varies from a light straw,
through amber red and brown to a dark green
and black. 1t is mixture of hydrocarbons or
compounds Of hydrogen and carbon, varying con-
aiderably, according to the locality in which it is
found, in both composition and consistency, and
Of two distinct varieties, asphalt base and parafn
base, with many constituents.
The more volatile and nlammable portions of
the raw product separated by refining, each
constituent being taken off and collected sep
arately by gradually raising the temperature of
the oil and passing the consequent vapors
gases through series Of condensers. The prod
ucts from the parafIn bases are usually taken off
as follows: Gasolines and naphthas, kerosene or
standard white as 1t is known, other illumi-
mating oils, light and heavy lubricating oils par
afin, and greases of various descriptions. The
percentage of each product recovered from the
crude varies according to the character of the
crude. fair average of Pennsylvania crude oil
ran follows: Gasoline, IL per cent; naphthas,
IA per cent; kerosene, 55 per cent; lubrcating
oils. IN per cent; paraffin, per cent; and residue
Of pitch, etc, 10 per cent. Many varieties of
eliminate sulphur and other Objectionable ele-
ments. From the asphat-base petroleum is de-
prived of residuum employed in the manufac-
ture OF insulating, water-proofing and roofing ma
terials A residuum known coke" Is also
used fuel and in the manufacture of carbons
for arc lights and electric batteries.
Along the banks Of stream In Pennsylvania,
now known under the prosaic title of OIL Creek.