126 



KNOWLEDGE 



[June 1,1898. 



trace the development of the modern drilling plant em- 

 ployed for the sinking of the oil wells, from the simple 

 hand-worked appliances which, first used in the States 

 for the sinking of brine wells, have become gradually 

 superseded by the rapid and beautiful drilling plant com- 

 prised in what is known as the " American system." This, 

 although not the only system in use, will be described as 

 representative. 



The first necessity is the "derrick" — a strong wooden 

 framing resembling the structure at the pit-head of a 

 colliery, and serving to support and control the working 

 of the string of drilling tools. The derrick varies in height 

 from about thirty feet, in the case of shallow wells, to 

 seventy feet, in the case of the deeper wells, and the drilling 

 tools are suspended from it on a stout rope, which is operated 

 by an engine to raise and lower the tools. Somewhat com- 

 plicated in their construction, the drills act by giving a blow 

 at the bottom of the boring each time they are allowed to 

 descend. A special appliance known as the "jars" is 

 arranged to prevent the drill becoming jammed. It con- 

 sists of two parts which slide upon each other and give a 

 jar to the tool on the up-stroke, so that any tendency to 



"torpedoing" — at the bottom of the well, in order to loosen 

 the strata, and so facilitate the oil's access to the well. 

 The oil is either pumped, or flows naturally, into a tank, 

 from which it is conveyed by pipe lines to the refineries, 

 as will be described later on. 



V\\-\\ after being " torpedoeil." A f^ule Dieeliarj 



jam is overcome. The total weight of a set of drilling 

 tools is nearly four thousand pounds, and, in addition to 

 this, a series of ingenious tools known as " fishing tools" 

 has to be provided for finding and raising any part of the 

 drilling tools which may become detached and remain in 

 the well. 



At intervals the tools are withdrawn, and the sand pro- 

 duced by the drilhng is removed by pumps or balers. 

 As the well is sunk it is cased throughout with metal 

 tubing to avoid choking up by detritus or caving-in of the 

 strata. 



When the oil stratum is struck, or, more usually, when 

 the well begins to show a decreased yield, it is common 

 in America to explode a charge of dynamite — known as 



ECONOMIC BOTANY. 



By John R. Jackson, a.l.s., etc., Kce/ier of the Mtiseums, 

 Roi/al Gardens, Keiv. 



PAPAVERACE/E.— Though this is a comparatively 

 small order in the number of genera and species, 

 and though the plants themselves are of the nature 

 of small herbs, the order is one of considerable 

 economic importance and interest. The plants 

 are natives of temperate climates, particularly of Europe, 

 and are well marked by their narcotic properties. By far 

 the most important plant of the family is the opium poppy 

 [I'apnvei- sornniferum), which, though it cannot be said to 

 be known at the present time in a truly wild state, is 

 probably a native of South-Eastern Europe and Asia Minor. 

 The poppy has been cultivated from 

 early antiquity for the sake of its 

 dried juice, well known as opium. 

 It is now very widely spread, but 

 Asia Minor, Egypt, Persia, and India 

 yield the principal supply ; China 

 also yields a large quantity. In Asia 

 Minor, from whence the best opium 

 used in medicine is obtained, the 

 juice is collected by making incisions 

 around the circumference of the 

 poppy head or fruit while the plants 

 are yet growing. The milky juice 

 exudes slowly, soon becoming plastic 

 or semi-solid, and turning brown; it 

 is scraped ofi" with a knife and placed 

 on a leaf of dock {liumex), which is 

 carried in the left hand by the 

 collector. When sufficient has been 

 thus obtained to form a moderate- 

 sized lump it is rolled up in the leaf 

 and allowed to harden. In India 

 the mode of collection is somewhat 

 different ; the fruits are scarified 

 longitudinally by a kind of small 

 lancet, the juice is scraped ofi' in little 

 scoops, and poured into bowls, in 

 which part of the moisture separates. 

 In the factory it is mixed or stirred 

 in vats to insure uniformity of sub- 

 stance, and then made into balls 

 of about six inches diameter and 

 covered with the dry poppy petals. 

 In this condition it is stacked in racks in the opium store, 

 and when required for exportation to China it is packed in 

 chests divided into numerous compartments, each division 

 holding one ball. Indian opium contains a much lower 

 percentage of morphine than that from Asia Minor, and 

 is consequently of much less value for medicinal purposes. 

 It is, however, largely used for eating and smoking. 



The cultivation of the opium poppy in cool countries is 

 chiefly for the sake of the capsules and seeds, the former 

 for supplying the shops with " poppy heads" for making 

 fomentations for allaying pain as well as for making 

 syrup of poppies, and the latter for the sake of the oil they 

 contain, which, when clarified, is of a sweet nature and of 

 a pale straw colour, and is used for mixing with, or as a 



