MOTOR SPIRIT.

Hokitika Guardian, 2 December 1924, Page 3

MOTOR SPIRIT.

ROMANCE OF PETROL. As you travel by ’bus, charabanc, or for that matter, by any other form of motor transport, do you ever think of the romance of the fuel, petrol, which provides the power? (asks a London exchange). Among natural products, petroleum, the crude oil from which motor spirit i.s taken, occurs in every continent of the world, and new finds are being tapped every day to meet the tremendous and growing demand for its products. A popular fallacy regarding crude oil i.s that it is found in large underground ponds or pools. This is quite an error, as the oil is always contained in a porous stratum in the earth. This stratum consists of sand and limestone, and contains the oil as a sponge holds water. Naturally the oil-hearing stratum must lie between two strata of impervious material, such as clay or rock, otherwise all the oil would have leaked away and been lost ages ago.

ORGANIC OR INORGANIC. Some authorities hold that the oil is of organic origin—that it has been produced by the decay of vegetable matter, in the same way that, of prehistoric forests, hut under slightly different conditions. Others say that the formation is inorganic—that it has been framed by interaenoii of minerals.

As recently as 2it or .'lO years ago, in Rmunauia or Russia, wells were dug by hand, as when sinking for water. The oil was then hailed out with wooden or leather buckets, in exactly the same way as water is obtained in country villages to-day. In Roumnnia some of these wells were as dee)) as 150 feet, and were lined with wickerwork to prevent the walls caving ill.

This method, of course, could only reach oil comparatively near the surface. To-day. oil wells can he drilled by machinery to depths of a mill* and a half in search of deep-lying oilhearing strata, hut these wells are of much smaller diameter, being probably tin. to 12in. bore. The walls are lined with steel.

TWO .METHODS. There are two principal methods of drilling wells in operation to-day. First, the percussive system. A heavy drilling tool is hung oil the end of a wire cable, and alternately raised and dropped on In the earth or rock, thus pounding it into fragments. These fragments are at short intervals hailed out of till* hole in the form of mud. In the second system, a rotary drill is used, and the fragments ol earth are continuously washed to the surlaeo by keeping water cireiilaling down the drill rods and up the sides id the well.

When the oil-hearing stratum is reached, sometimes the oil Hows to Ihe top of the well under a violent pressure. The well is then known as a ‘'gusher.'’ and il the pressure is ver\ great the most slringent precautions have to he taken to keep the oil within hounds. At other times the oil does not reach the surface, and then, ill order to produce it, the well has to he continuously pumped. After the oil is obtained from tin* "■ell it has to he taken to the refinery in order that it may he divided into its various components and made suit - ilhle for commercial purposes.

This transport is usually ellected h,v pipe lines, which in some eases are ol enormous length. Ihe lammis line between Baku and Batoiim. in the Russian fields, is almost 5ti1.l miles in length. After arrival at the refinery, the crude oil is distilled. That is, it is heal"d in large vessels, and the vapour which boils oil' is condensed. Among the first vapours evolved is tl„. petrol known as “aviation spirit." \ 11,.|- the benzine or m/'lor spirit eoii.es the kerosenes, u-iiallv known as

Hill oil." The estimated "...Id's productimi -I pelioleiiin lor P.'2A was Ihirlv six million tons.