52 



l*Ot*tJLAR SClEi^CE NEWS. 



[April, 1889 



In other periods, like conditions existed, but not 

 to so great an extent. Hence we find only small 

 quantities of petroleum or gas in other formations. 



The oil formed in the limestones from animal 

 remains diifers considerably from that derived from 

 vegetable sources. It is found in pockets, usually 

 small, and in the cavities in corals, etc., the dense 

 rock preventing it from becoming generally diffused. 

 It is thus indigenous to the rock in which it is 

 found. 



On the other hand, the oil from vegetable sources 

 may be found far above the rock in which it was 

 formed, the vegetable remains being, for the most 

 part, in the open and porous formations, which 

 permit the oil and gas to be forced by the pressure 

 to which it was subjected, upward into any open- 

 grained rock or layer which they could reach. 



As we would expect, experience has shown that it 

 is useless to bore for oil or gas in a region where the 

 strata have been dislocated or broken, both having 

 long since escaped. Neither can they be found by 

 boring at the bottom of the trough of a synclinal, 

 because both oil and gas follow the trend of the 

 strata upward, and escape, unless confined by the 

 roof-like fold of an anticlinal. It has been found, 

 moreover, that wells bored at random, on the apex 

 of the anticlinal, are not uniformly successful ; they 

 must pierce the domes or high points of the eleva- 

 tion. This applies especially to the oil-fields of 

 Virginia and Canada. In Pennsylvania, oil, and 

 generally gas, saturate the porous portions of for- 

 mations that have suffered only a slight disturb- 

 ance, which affected large areas equally. These 

 formations have been forced from a horizontal posi- 

 tion to a very slight extent, and the slope of the 

 anticlinal is very gradual. The oil and gas always 

 occupy the highest portions of it, however; a well 

 sunk on the edge of the field usually affords only 

 salt water. 



The life of wells — both gas and oil — is usually 

 about five years, though some have been exhausted 

 in two; while others, as at Triumph Hill, in Penn- 

 sylvania, have been flowing for fifteen years. When 

 the flow of an oil-well diminishes or ceases, it is 

 customary to explode nitro-glycerine in it, or 

 "shoot it." This shatters the oil-rock and enables 

 oil to flow in from some distance in all directions. 



The gas obtained from these wells is ready for use 

 as a fuel, as it is found. Not so with the oil. It 

 must be "refined," as the process by which it is 

 separated into different compounds is called. Con- 

 ducted from the wells into immense tanks, it is 

 allowed to stand for a time, so that the water and 

 sediment, usually found in it, may settle. The oil, 

 thus purified, is drawn out of the tanks and carried, 

 usually by pipe lines, to the refineries, which are 

 frequently at considerable distances from the oil- 

 fields. The crude oil is forced through the pipes by 

 engines at pumping-stations along the line, under a 

 pressure of from fifteen hundred to sixteen hundred 

 pounds to the square inch. 



At the refinery the oil is allowed to stand in large 

 tanks, to remove a very small percentage of water 

 and sediment still remaining. From these tanks it 

 is conducted into stills, holding from forty to fifty 

 thousand gallons, into which steam is turned. Dis- 

 tillation commences at once, naphtha passing over; 

 when the naphtha has been driven off, the tempera- 

 ture is raised, and illuminating oil is driven over 

 and condensed. It is of the greatest importance that 

 the illuminating oil, or kerosene, contain no naph- 

 tha, one to five per cent, of which renders it danger- 

 ously explosive. The heat may now be moderated, 

 distillation allowed to proceed slowly, the vapor 

 generated being confined in the still. By this means 

 the oil is "cracked," or broken up, into marsh-gas, 



hydrogen, crude naphtha, crude petroleum, and a 

 tarry residue. The naphtha and oil are purified and 

 separated by distillation; the residue is sold to man- 

 ufacturers of lubricating oil, and the gas is led off 

 and burned. If the oil is not to be cracked, the 

 heavy oil from which naphtha and kerosene have 

 been removed, is distilled at a high temperature, 

 until all the lubricating oil which it contains has 

 been driven off. From the cooled residue, paraffin 

 is removed by pressure, and from the oil left, "min- 

 eral sperm" is obtained. 



When a high grade of illuminating oil is desired, 

 that obtained by distillation is further purified by 

 washing with sulphuric acid. After being thorough- 

 ly mixed with the oil, the spent acid is allowed to 

 settle to the bottom, and is drawn off to form part 

 of a valuable fertilizer. 



Besides the commercial products derived from pe- 

 troleum mentioned above, there are a number of 

 others — among them, rhigolene, the lightest and 

 most volatile of the series, used in surgery to pro- 

 duce local aniEsthesia; gasoline, used to produce 

 "carburetted air," an illuminant in places where 

 coal-gas is not to be obtained ; petroline, cosmoline, 

 etc., used in pharmacy as vehicles for ointments, 

 and especially valuable for this purpose, because they 

 never become rancid ; and paraffin oil. Aniline 

 and aniline colors are not obtained from petroleum, 

 as is generally believed, but from the waste products 

 of the manufacture of illuminating gas. E. 



[Original in The Popular Science News.] 

 TO WHICH KINGDOM DO THEY BELONG.' 



BY M. J. GORTON. 



On any land-locked and sheltered pool of water, 

 where the food for life is supplied from the condi- 

 tions of the lakelet, there inay be found organisms 

 of plant life, or organisms of animal life, so nearly 

 allied — the different growths with so many attributes 

 of restless activity, and supplied in each case, each 

 with the properties of the other — that it may be 

 found to be a matter of interesting research to 

 trace analogies and to note differences, and to ob- 

 serve the many variations and changes in micro- 

 scopic insect life. 



It has been demonstrated that there are certain 

 organisms which pass through a monad state of ex- 

 istence, and which, at one time in their lives, are 

 dependent upon external sources for their protein 

 matter, or are animals, having all the adjuncts of 

 animal life, and fulfilling the full requirements of 

 animal life, and at another time manufacture their 

 protein matter like plants. The true parasitic 

 plants go yet farther, and put together material still 

 better prepared, and that more nearly approximates 

 protein, until from myosmycetes we arrive at such 

 animals as the Psorospermia, which, says the author 

 of Lay Sermons, "are as much animal as vegetable 

 in their structure, but are animal in their dependence 

 on others for food." 



Going a little higher in the scale, we find organs 

 and the necessary appurtenances of the finest mech- 

 anism, created for the purpose for which they are to 

 be applied. The larva of the common gnat, which 

 may be found on any of our still-water pools, is fur- 

 nished with respiratory organs, aided by doors of the 

 •most ingenious mechanism, which the insect opens 

 or shuts at will. It only opens them when it comes 

 to the surface of the pool to breathe ; on the con- 

 trary, when it plunges into the water, the leaves of 

 this air-door are closely shut, and the pneumatic 

 channels are thus defended against the entrance of 

 the liquid. To obtain larva for investigation, place 

 an open glass fruit-jar in the open air, in a spot of 

 deep shadow, when the spring is far enough ad- 

 vanced to be warm and moist, and in one night's 

 time, usually, there will be found the small white 



larva dots, which, if brought in-doors, soon develop, 

 and afford much instruction to the observing micro- 

 scopist. The mosquito {Culex pipiens) and the 

 gnat are of the same genus. On the roadside pools, 

 and upon the surface of the standing water to be 

 found in deserted quarries, where the water becomes 

 quite warm, there are to be seen often floating 

 islands of white larva, which the country-side, ever 

 observant and quick to note resemblances between 

 the kno'wn and the unknown, call the rat-tailed 

 maggot. 



Put this rather repulsive and quite ungainly creat- 

 ure under the microscope, and it will be found that 

 the extraordinary appendage or tail, to which the j 

 organism owes its name, is its breathing apparatus. 1 



There are two canals, which allow the passage of 

 air all through the body of this fly-larva. Careful 

 observation will bring to notice this curious fact : 

 that these two aerial tubes are of different sizes, and 

 that the smaller one slides into the one of larger j 

 calibre, and moves in and out exactly like the tubes ' 

 of a telescope. 



Take this creature, which is without any swim- 

 ming appliances, and place in a shallow glass dish, 

 with but little water in It. Gradually fill the glass, 

 and, as he finds the water vary in depth, he elongates 

 his tubes, exactly as the tubes of the telescope are 

 lengthened, thus keeping his mouth above water. 

 Draw the water off, and, as the water falls, he draws 

 in his tubes, and the aerial tubes wind up inside of 

 them. Jar the vessel, and it will be found that the 

 animal's tail will lengthen in proportion to the depth 

 of the water, even to an extraordinary length, so 

 that, without quitting the spot, it may still breathe 

 by resting its respiratory organ on the surface of the 

 water. 



Another very interesting experiment is to feed 

 microscopicanimalcula. Take full-sized colpoda", the 

 largest specimens of which attain a length of onl\ 

 one three-hundredth of an inch, and if coloring 

 matter, say indigo or carmine, is thrown into the 

 water, and the lens arranged to observe them, 

 they can be observed as easily as so many rab- 

 bits feeding. Soon their bodies, which are trans- 

 parent, are seen to be stuffed with the deeply-colored 

 particles of the coloring matter. 



To test the matter to the satisfaction of the most 

 doubtful observer, let him take another well-known 

 animalcule, the Paramacium, which is very much 

 larger than the colpodae. It reaches one one-hundred- 

 and-twentieth of an inch or more in length, and 

 there is no difficulty in making out its physical 

 appendages. Feed these animals on highly-colored 

 matter, and watch the particles of indigo or carmine 

 pass into the transparent body. With many charac- 

 teristics of plant li^'e, this complex creature multi- 

 plies by division, as the monad does, and, like the 

 monad, undergoes conjugation. Start from either 

 side, and observe the phenomena as it occurs, and 

 so insensible are the gradations — the series varying 

 almost insensibly — that it is with less and less assur- 

 ance that it can be said, "here the line between the 

 plant and the animal can be drawn." 



Says a noted author on this topic: "The won- 

 derful facts which have recently been brought to 

 light respecting insectivorous plants, tend to the 

 conclusion that the difference between animal and 

 plant is one of degree, rather than of kind, and that 

 the problem whether, in a given case, an organism 

 is a plant or an animal, may be essentially insol- 

 uble." 



That power of contractility, which is the basic 

 condition of animal locomotion, is found among 

 plants, and such contraction has been found to be 

 accompanied, as Dr. Burdon Saunderson's interest- 

 ing investigations have shown, by a disturbance of 

 the electrical state of the contractile substance. 



