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Scientific American Supplement, No. 430, March 29, 1884
Author: Various
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It is evident, a priori, that a perfect apparatus will be the one that will allow the light to act during the entire exposure with a maximum of intensity. Is it thus, when the aperture is equal to the diameter of the objective? Evidently not. Let us consult Fig. 2. We here see the shutter progressively uncovering the objective. The light will increase from A to C up to the moment when the objective is entirely uncovered, and will then immediately decrease up to B. The objective has operated with a maximum of light for only a short time. We are far from the ideal result in which the maximum of light, CD, should exist during the entire exposure, and form the upper plane precisely equal to AB.



If we cannot obtain such a result in practice, we must nevertheless aproximate to it. We shall do so by increasing the shutter. Up to C' the apparatus will operate as before, but from C' to D' the aperture will be complete, and from D' to B' will decrease as has been said.

Let us give A'B' the same value as AB, that is to say, let us increase the velocity in the second case in order that the time of exposure shall be the same; we shall at once see that in the first case the object will be completely uncovered for only a very short time, while in the second the exposure will be perfect for a very appreciable period.

The time of exposure which is absolutely active, we propose to call effective time of exposure in contradistinction to the total time of the same. The more we increase the value of C'D', that is to say, that of the effective time, the more the ratio, C'D'/A'B', will approximate to unity, and the nearer we shall reach perfection. The correlative of such elongation of the aperture is an increase in velocity which will always bring the total exposure to the same figure, whatever be the aperture employed.

If the aperture be equal to two diameters, the effective time will be equal to half the time of the total exposure; and if it is equal to three diameters, the exposure will be good during 2/3 of the total time. This amounts to saying that the effective time of exposure is equal to n times the diameter—1, the velocity being supposed always uniform. If we place the shutter within the objective, it is the diameter of the diaphragm that it will be necessary to say. The effective time will be equal then to n diaphragm—1.

From what precedes it results that in no case should the aperture be inferior to the diaphragm, since the former would otherwise absolutely suppress the effective time in giving a lower plane corresponding to an insufficient quantity of light. Moreover, an aperature of this kind would prove injurious to the quality of the image by successively uncovering rays which do not form their image identically at the same point. We are now, then, in presence of results that are absolutely positive, and they are as follows:

1. The guillotine shutter should be placed in the interior of the objective and as near as possible to optical center, that is to say, behind the diaphragm, since the latter is precisely in the optical center.

2. The aperture should be as wide as possible.

3. The velocity should be as great as possible.

In practice, an aperture from 4 to 5 times the diameter of diaphragm employed will be more than sufficient, since we shall have, according to circumstances, 3/4 or 4/5 of the effective time. Moreover, whatever be the time of exposure, this ratio once established will be invariable, and the apparatus will always operate identically.

A shutter combining these qualities will not yet be perfect. It is necessary, according to the time and the light, that the time of exposure shall be capable of being varied. In a word, it is necessary that the apparatus shall be graduated and permit of taking views more or less quickly. The different velocities might be given to the shutter by means of weights, rubber, or springs. The latter seem to be preferable, since they permit in the first place of operating out of the vertical; moreover, they are less fragile, and, through different tensions, they permit of these graduations that we consider as indispensable. For the current needs of practice 1/100 of a second is a limit that seems to us sufficient as a maximum of rapidity. In order to know the time of exposure obtained we employ the following method, which permits of graduating an apparatus rapidly and with extreme precision:

A band of smoked paper is fixed upon the shutter, then a tuning-fork provided with a small stylet resting against the paper is made to vibrate. Better yet, a chronograph which vibrates synchronously with a tuning-fork, whose motion is kept up by electricity, is put in the same place. Fig. 3 shows the arrangement to be employed. We then let the shutter fall, when the little stylet will inscribe a certain number of vibrations. Knowing the number of vibrations of the tuning-fork, and counting the number of those inscribed upon the paper, it is very simple to deduce therefrom the amount of the time of exposure. The results of one of these experiments we have reproduced in Fig. 4. The tuning-fork gave 100 double vibrations per second. Six vibrations are included between the opening and closing of the apparatus. Each vibration estimated at 1/100 of a second. The exposure was 6/100 of a second in round numbers. This is the amount of the total time of exposure. As for that of the effective time, that is just as easily ascertained. It suffices to know the number of vibrations comprised between the moment at which one point of the objective has been completely uncovered and that at which it has begun to be covered again. The time is equal to 2/100 in round numbers.

In the experiment in question, with an aperture equal to twice the diameter of the diaphragm, we have, then, 1/3 of the half-open exposure; and the amount of the effective time is 1/3. The difference that we have in practice is due to the fact that the velocity is uniformly accelerated. In order to increase the amount of the effective time, it will be only necessary to increase the aperture of the shutter and apply again the method that we have just pointed out.



So much for the material part of the apparatus. It will be necessary in addition to acquire sufficient individual experience to be able to estimate the intensity of the light, and consequently to judge of the diaphragm to be employed and the velocity to be obtained. It must not be forgotten that such or such an object having a relatively slow speed will not be sufficiently sharp on the negative if it is too near the apparatus, while such or such another, much more rapid, might nevertheless be caught if sufficient distance intervened. Here it is that will appear the skill of the amateur, who will find it possible to obtain the said object as large as possible and with a maximum degree of sharpness.

We have seen what diverse qualities should be possessed by a good guillotine shutter, and it is evident that the same should be found in all apparatus of the kind. In our opinion the guillotine is a well defined type that possesses one capital advantage, and that is that it permits of the use of aperatures as wide as may be desired for the same time of exposure. It is a question, as we have seen, of velocity. Consequently, however short the exposure be, it will always be possible to operate with a full amount of light during the greater part of the exposure. It is necessary to dwell upon this point, since in another kind of apparatus that possesses a closing and opening shutter the same result cannot be reached. In the Boca apparatus, for instance, we remark that at a given moment the time of exposure is reduced to nothing, as the closing shutter covers the objective before the latter has been unmasked by the opening one. In all exposures, in fact, the times of opening and closing have a constant value. It follows that the shorter the exposure is, the greater becomes such value, and to such a point that, at a given moment, the apparatus no longer make an exposure.



In the guillotine, on the contrary, the same space always intervenes between the time of opening and closing, since it is fixed in an unvarying manner by the diameter at the aperature. Then, the greater the velocity, the more the time of opening and closing diminishes. If the ratio of the effective to the total time of exposure is 3/4, for example, it will be invariable, whatever be the velocity.

In concluding, we will remark that, without employing springs, we may increase the aperture of the shutter without varying the time of exposure. To effect this it is only necessary to raise the point of the shutter's drop. In fact, as may be seen in Fig. 4, all the vibrations of the stylet corresponding to 1/100 of a second always continue to elongate, and it will consequently be possible for the same time of exposure to considerably increase the aperture and, as a consequence, the effective time, by causing the guillotine to drop from a greater elevation. From this study, which has principally concerned the guillotine shutter, can we draw the deduction that this type of apparatus will become a definite one? We think not. In fact, along with its decided advantages the guillotine has a few defects that cannot be passed over in silence. The aperture, in measure as it is increased, renders the apparatus delicate and subject to become bent. If, in order to obviate this trouble, we employ plates of steels, we increase its weight considerably, and the chamber becomes subject to vibration at the moment the shutter drops. If rubber or springs are used for increasing the velocity, it is still worse. Moreover, it is quite difficult to obtain a graduation, and to our knowledge, and probably for this reason, it has not yet been applied.

The reader will please excuse us for this perhaps somewhat dry theoretical expose, but we have thought it well to give it in the hope that it might well show the qualities that should be required of a photographic shutter and particularly of the guillotine. Moreover, at the point to which photography has arrived it is no longer permitted to do things by halves.

After the memorable discoveries of Nicephore, Niepce, Daguerre, and Talbot, photography remained for some time stationary, limited to the production of portraits and landscapes. But for a few years past it has taken a new impetus, and new processes have come to the surface. In the graphic arts and in the sciences it has taken considerable place. Being the daughter of chemistry and physics, it is not astonishing that we require of it the precision of both. It is, moreover, through a profound study of the reactions that gave it birth and through a knowledge of the laws of optics that it has come into current use in laboratories. In fact, it alone is capable of giving with an undoubted character of truthfulness a durable vestige of certain fleeting phenomena.—

A. Londe, in La Nature.

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FALCONETTI'S CONTINUOUSLY PRIMED SIPHON.

To carry a watercourse over a canal, river, road, or railway, several methods may be employed, as, for example, by aqueducts like those of Arcueil and Buc near Versailles, and by upright and inverted siphons. Of these three means, the first is the most imposing, but is also very costly; and, besides, the declivities as well as the arrangement of the ground are not always adapted thereto. The inverted siphon is subject to obstruction and choking up in its most inaccessible parts, while the upright siphon is easy of inspection, taking apart, etc. But, per contra, the latter loses its priming very easily by reason of the formation of air spaces.



Mr. Falconetti, an inspector of bridges and roadways, has found a means of rendering the latter occurrence impossible by an arrangement which is both simple and practical, and which is illustrated herewith. In the figure, a and b are the two vertical legs of the siphon, both of which enter the liquid. These open into the receptacles, c and d, in which the cocks, e and f, cut off or set up a communication with the pipes, a and b. These latter are connected by a branch, g, which may be put in communication with a reservoir, h, that is divided into two superposed compartments by a partition, i. Such communication may be established or cut off by a valve, j, maneuvered by a key, k, which traverses an aperture in the partition, i. Another aperture, m, in this same partition serves to put the two parts of the reservoir, h, in communication, and, for this purpose, is provided with a cock, n, which is easily maneuvered from the exterior.

The object of this arrangement of cocks and reservoir is to prevent the siphon from losing its priming through the possible presence in the transverse portion of a certain quantity of air or gas that might be given off by the water and accumulate in this place.

The compartment, A, of the reservoir, h, is designed for receiving the gases that collect in the top of the siphon, while the upper compartment contains water for making a hydraulic joint, and consequently preventing any re-entrance of air through the apertures in the partition, i.

To prime the siphon, we shut the cocks, e and f, open the valves, j and m, and pour in water until the whole affair (siphon and reservoir) is full; then we close the cock, m, and open the three others. The siphon thus becomes primed, and begins to operate as soon as any water reaches one or the other of the lower receptacles. As the cock, j, is constantly turned on during the operation of the siphon, the air that has been able to accumulate in the lower compartment, A, of the reservoir, h, would finally unprime the siphon by intercepting communication between its two legs. In order to prevent such a thing from occurring, it suffices to expel the air, from time to time, that accumulates in the chamber, A, this being done, without stopping the operation of the siphon, as follows:

After closing the cock, j, water is poured into the reservoir, and, running down to the lower compartment, drives out the air through the cock, m. This operation once effected, it only remains to turn off the cock, m, again, and open j in order to establish the normal operation. As the chamber, A, is provided externally with a water gauge, N, it may be seen at a glance when it is necessary to maneuver the cocks in order to expel the air.

This system of siphon is evidently applicable to all sorts of liquids. It may likewise undergo a few modifications in its construction; for example, the valve, which in our engraving is placed over the siphon, may be located at any distance from the apparatus, although it should, in all cases, be in constant communication with it by means of a tube, and be placed a little higher than the siphon. It may then be put under cover and be kept constantly in sight, thus greatly facilitating its surveillance.

As may be seen, the essential peculiarity of this improvement consists in the very ingenious arrangement that permits of immersing the cocks in the liquid to make them perfectly tight, it being necessary that they should be hermetically closed in order to prevent the entrance of air to the siphon. Everything leads to the belief, then, that if upright siphons have never been able to operate regularly, it has been because no means have been known of expelling the air from the interior without letting air from the exterior enter at the same time. The arrangement devised by Mr. Falconetti gets over the difficulty in a very elegant manner. It seems as if it would be called upon to render great services in the industries, and it well merits the attention of engineers of roads and bridges, and of contractors on public works.—Revue Industrielle.

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THE WEIBEL-PICCARD SYSTEM OF EVAPORATING LIQUIDS.

In the industries, there are often considerable quantities of liquid to be evaporated in order to concentrate it. Such evaporation is very often performed by burning fuel in sufficient quantity to furnish the liquid the heat necessary to convert it into steam. This process is attended with a consumption of fuel such as to form a very important factor in the cost of the product to be obtained. In order to vaporize, at the pressure of the atmosphere, 1 kilogramme of water at 0 deg., 637 heat units are required, and of these, 100 are employed in raising the water from 0 deg. to 100 deg. and 537 in converting the water at 100 deg. into steam at 100 deg.. This second quantity is called the latent heat of the steam at 100 deg.. The sum of the two quantities is called the total heat of the steam at 100 deg.. The total heat of the steam remains nearly constant, whatever be the temperature at which the vaporization occurred.



In order to utilize the steam as a means of heating, it is necessary to condense it, that is to say, to cause it to pass from the gaseous to a liquid state. This conversion disengages as much heat as the passage from the liquid to the gaseous state had absorbed.

It results from this that if we could condense the steam that is given off by a liquid that we are vaporizing, in contact with another liquid that it is also a question of vaporizing, we should utilize all the heat contained in the steam that was being given off from the first.

This object can be practically attained by two means, viz., by (1) putting the disengaged steam in contact with the sides of a vessel that contains a liquid colder than the one that produced it; (2) by raising the temperature and pressure of the disengaged steam in order to condense it in contact with the sides of the vessel which contains the very liquid that has produced it.

The first of these means is realized in the apparatus called multiple acting, that are at present so generally employed in sugar works. The second means, which permits of a greater saving in fuel being made than the other does, is realized by compressing the disengaged steam. This compression, which raises the temperature and pressure of the steam, permits of condensing the latter in contact with the vessel wherein it has been produced. By such condensation we continuously restore to the liquid which is being vaporized the heat of the steam which it gives off.

This solution of the question, which has been partially seen at different epochs, has but recently made its way into the industries. It is being operated at present with complete success at the salt works of France and Switzerland, at those of Austria and Prussia, in the sugar of milk factories of France and Switzerland, and, finally, in 1882, the first application of it in the sugar industry was made at Pohrlitz, in Moravia.

The saving of fuel that has been made in these different applications has always been great.

We shall now, for the sake of explaining the system, give a brief description of the apparatus as used at the Pohrlitz sugar works mentioned above. These works treat 255 tons of beets per 24 hours, and obtain 4,000 hectoliters of juice, which is reduced to about 1,000 hectoliters of sirup. Up to the present, the concentration has been effected in a double acting apparatus partly supplied by exhaust steam from the motive engines and partly by steam coming directly from the generators.

In order to diminish the consumption of direct steam, these sugar works put in a Weibel-Piccard apparatus designed to concentrate only a third of their juice, or about 1,350 hectoliters per day.

This apparatus (see engraving) consists of a steam compressor, 0.835 m. in diameter, actuated directly by a driving cylinder of 0.5 m. diameter and 0.8 m. stroke, and of three evaporating boilers of the ordinary vertical tube type, the first of which has a surface of 150 square meters, the second 60, and the third 80.

The steam, at the ordinary pressure of the generators, say 5 atmospheres, is taken from the connected generators of the works, and is led to the driving cylinder, where it expands and furnishes the power necessary to run the compressor. It then escapes at a pressure of l.4 atmospheres and enters the intertubular space of the first evaporator. The compressor sucks up the steam from the juice of the first evaporator (which is boiling at the pressure of the atmosphere, without vacuum or effective pressure), compresses it to 1.4 atmospheres, and forces it likewise into the intertubular space. The ebullition of the first evaporator, then, is kept up not only by the exhaust from the motive cylinder, but also by the steam from the juice itself, which has been rendered fit to serve as a heating steam by the pressure that it has undergone in the compressing cylinder.

In this first application of the new system to sugar making, it became a question of ascertaining whether the advantage resulting from compression was of great importance, and, in the second place, whether the apparatus could be run with certainty and ease. In truth, the applications of the system for some years past in other industries permitted a favorable result to be hoped for, and the result turned out as was expected.

With this apparatus it has been found that the work furnished by one kilogramme of steam passing through the motive cylinder, from a pressure of 5 atmospheres to one of 1.4, is sufficient to compress 2.5 kilogrammes of steam taken from the juice, led into the compressor at one atmosphere and escaping therefrom at 1.4. In other words, one kilogramme of motive steam is sufficient to convert into heating steam for the first evaporator 2.5 kilogrammes of steam taken from the juice in this same evaporator. Besides, this same kilogramme of motive steam produces three effects, one in this same evaporator, and the other two in the two succeeding ones. The effect obtained, then, from one kilogramme of motive steam is, in round numbers, 5.5 kilogrammes of steam removed from the juice.

It must not be forgotten that the motive steam was at the very moderate pressure of 4 effective atmospheres. Had the use of steam at high pressure (7 atmospheres for example) been possible, it is easy to conclude from the above results that more than 6 kilogrammes of water would have been vaporized with one kilogramme of steam.

The results here cited were ascertained by accurately measuring the quantities of water of condensation from each evaporator, they soon received, moreover, the most important of confirmations by the decrease in the general consumption of fuel by the generators which occurred after the new apparatus was set in operation.

The mean consumption of coal per 24 hours for the twenty days preceding the 18th of November was 86,060 kilogrammes. After this date the regular consumption was as follows:

Nov. 19.................31,800 kilogrammes. " 20.................33,800 " " 21.................33,800 " " 22.................32,000 " " 23.................31,400 " " 24.................31,600 " " 25.................30,500 " " 26.................30,500 " " 27.................28,600 " " 28.................30,300 "

It must be remarked that in the perfectly regular running of the sugar works, nothing was changed saving the setting of this evaporating apparatus running. The same quantity of beets was treated per 24 hours, and the general temperature remained the same. This remarkable result in the saving of fuel was brought about notwithstanding the new apparatus treated but a third, at the most, of the total amount of the juice, the rest continuing to be concentrated by the double action process.

As for the running of the apparatus, that was perfectly regular, and the deviations in temperature in each evaporater were scarcely two or three degrees. The following are the mean temperatures:

First evaporator: heating steam 110 deg. C.; juice steam 100 deg. C. Second evaporator: juice steam 83 deg. C. Third evaporator: juice steam 62 deg. C. As regards facility of operating the apparatus, the experiment has proved so conclusive that the plant will be considerably enlarged in view of the coming crop, in order that a larger quantity of juice may be treated by the new process. The effect of this will be to still further increase the saving in coal that has already been effected by the present apparatus. The engraving which accompanies this article represents the Weibel-Piccard apparatus as it is now working in the Pohrlitz sugar works. What we have said of it above we think will suffice to make it understood without further explanation.—Le Genie Civil.

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COMPARISON OF STRENGTH OF LARGE AND SMALL ANIMALS.

W. N. LOCKINGTON.

M. Delebeuf, in a paper read before the Academie Royale de Belgique, and published in the Revue Scientique, reviews the attempts of various naturalists to make comparisons between the strength of large animals and that of small ones, especially insects, and shows that ignorance or forgetfulness of physical laws vitiates all their conclusions.

After a plea for the idea without which the fact is barren, M. Delbeuf repeats certain statements with which readers of modern zoological science are tolerably familiar, such as the following: A flea can jump two hundred times its length; therefore a horse, were its strength proportioned to its weight, could leap the Rocky Mountains, and a whale could spring two hundred leagues in height. An Amazon ant walks about eight feet per minute, but if the progress of a human Amazon were proportioned to her larger size, she could stride over eight leagues in an hour; and if proportioned to her greater weight, she would make the circuit of the globe in about twelve minutes. This seems greatly to the advantage of the insect. What weak creatures vertebrates must be, is the impression conveyed.

But the work increases as the weight. In springing, walking, swimming, or any other activity, the force employed has first to overcome the weight of the body. A man can easily bound a height of two feet, and he weighs as much as a hundred thousand grasshoppers, while a hundred thousand grasshoppers could leap no higher than one—say a foot. This shows that the vertebrate has the advantage. A man represents the volume of fifteen millions of ants, yet can easily move more than three hundred feet a minute, a comparison which gives him forty times more power, bulk for bulk, than the ant possesses. Yet were all the conditions compared, something like equality would probably be the result. Much of the force of a moving man is lost from the inequalities of the way. His body, supported on two points only when at rest, oscillates like a pendulum from one to the other as he moves. The ant crawls close to the ground, and has only a small part of the body unsupported at once. This economizes force at each step, but on the other hand multiplies the number of steps so greatly, since the smallest irregularity of the surface is a hill to a crawling creature, that the total loss of force is perhaps greater, since it has to slightly raise its body a thousand times or so to clear a space spanned by a man's one step.

By what peculiarity of our minds do we seem to expect the speed of an animal to be in proportion to its size? We do not expect a caravan to move faster than a single horseman, nor an eight hundred pound shot to move twelve thousand eight hundred times farther than an ounce ball. Devout writers speak of a wise provision of Nature. "If," say they, "the speed of a mouse were as much less than that of a horse as its body is smaller, it would take two steps per second, and be caught at once." Would not Nature have done better for the mouse had she suppressed the cat? Is it not a fact that small animals often owe their escape to their want of swiftness, which enables them to change their direction readily? A man can easily overtake a mouse in a straight run, but the ready change of direction baffles him.

M. Plateau has experimented on the strength of insects, and the facts are unassailable. He has harnessed carabi, necrophori, June-beetles (Melolontha), and other insects in such a way that, with a delicate balance, he can measure their powers of draught. He announces the result that the smallest insects are the strongest proportioned to their size, but that all are enormously strong when compared bulk, for bulk, with vertebrates. A horse can scarcely lift two-thirds of its own weight, while one small species of June-beetle can lift sixty-six times its weight; forty thousand such June-beetles could lift as much as a draught-horse. Were our strength in proportion to this, we could play with weights equal to ten times that of a horse.

This seems, again, great kindness in Nature to the smaller animal. But all these calculations leave out the elementary mechanical law: "What is gained in power is lost in time." The elevation of a ton to a given height represents an expenditure of an equal amount of force, whether the labor is performed by flea, man, or horse. Time supplies lack of strength. We can move as much as a horse by taking more time, and can choose two methods—either to divide the load or use a lever or a pulley. If a horse moves half its own weight three feet in a second, while a June-beetle needs a hundred seconds to convey fifty times its weight an equal distance, the two animals perform equal work proportioned to their weights. True, the cockchafer can hold fourteen times its weight in equilibrium (one small June-beetle sixty-six times), while a horse cannot balance nearly his own weight. But this does not measure the amount of oscillatory motion induced by the respective pulls. For this, both should operate against a spring.

A small beetle can escape from under a piece of cardboard a hundred times its weight. Pushing its head under the edge and using it as a lever, it straightens itself on its legs and moves the board just a little, but enough to escape. Of course, we know a horse would be powerless to escape from a load a hundred times its own weight. His head cannot be made into a lever. Give him a lever that will make the time he takes equal to that taken by the insect, and he will throw off the load at a touch. The fact is that in small creatures the lack of muscular energy is replaced by time.

Of two muscles equal in bulk and energy the shortest moves most weight. If a muscular fiber ten inches in length can move a given weight five inches, ten fibers one inch long will move ten times that weight a distance of half an inch. Thus smaller muscles have an absolutely slower motion, but move a greater proportional weight than larger. The experimenter before mentioned was surprised to find that two grasshoppers, one of which was three times the bulk of the other, leaped an equal height. This was what might be expected of two animals similarly constructed. The spring was proportioned to the bulk. In experiments on the insects with powerful wings, such as bees, flies, dragon-flies, etc., it was found that the weight they could bear without being forced to descend was in most cases equal to their own. In some cases it was more, but the inequality of rate of flight, had it been taken into the reckoning, would have accounted for this.

Take two creatures of different bulk but built upon exactly the same plan and proportions, say a Brobdingnagian and a Lilliputian, and let both show their powers in the arena. Suppose the first to weigh a million times more than the second. If the giant could raise to his shoulder, some thirty-five feet from the ground, a weight twenty thousand pounds, the dwarf can raise to his shoulder, not, as might be thought, a fiftieth of a pound, but two full pounds. The distance raised would be a hundred times less. In a race the Lilliputian, with a hundred skips a second, will travel an equal distance with the giant, who would take but a skip in a second. The leg of the latter weighs a million times the most, but has only ten thousand times as many muscle fibers, each a hundred times longer than those of the dwarf, who thus takes one hundred skips while the giant takes one. The same physical laws apply to all muscles, so that, when all the factors are considered, muscles of the same quality have equal power.—Am. Field..

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OIL IN CALIFORNIA.

J.W. McKinley, writing to the Pittsburg Dispatch, gives the following account of the California oil field at Newhall:

On the edge of the town is located the refinery of the company, connected by pipe lines with the wells, a few miles distant. Leaving Newhall, we drove to Pico Canon, the principal producing territory of the region. As we approached, we saw, away up on the peaks, the tall derricks in places which looked inaccessible; but no spot is out of reach of American enterprise and perseverance. In one of the wildest spots of the canon, about thirty men were making the mountains echo to the strokes of their hammers upon the iron plates of a new 20,000 barrel tank. Along the canon are scattered the houses of the employes of the company, most of whom have recently come from Pennsylvania. Near one of the houses was a graded and leveled croquet ground, with a little oil tank on a post, for lighting it at night. Farther up we came to a cluster of producing wells, with others at a little distance on the sides of the mountains, or even at the top, hundreds of feet above our heads.

The first well was put down about eight years ago, but more has been accomplished in the last two years than in all the time previous. One well which we visited has produced 130,000 barrels in the last three years, and is still yielding. There have been no very large wells, the best being 250 per day, and the average being about 90 barrels, but they keep up their production, with scarcely any diminution from year to year. Drilling has been found difficult, as a great portion of the rock is broken shale lying obliquely. The tools slip to one side very easily, and a number of "crooked holes" have resulted. One driller lost his tools altogether in a well, and finished it with new ones. The cost of putting down a well is from $5,000 to $7,000, depending upon depth, etc. Most of the wells are from 1,200 to 1,500 feet, but some have yielded at a much less depth. One well of 270 feet depth produced 40 barrels per day for about three years, has been deepened, and is now yielding even more. Another one of 800 feet is said to have produced 200,000 barrels in the last five or six years. Drilling has been very successful in striking oil in paying quantities wherever there were indications of its presence.

The Pacific Oil Company now has 27 wells producing or drilling, and during the last two years has been rapidly widening the scope of its operations. It has now from 30 to 40 miles of pipe lines, and is preparing to lay 20 miles more, to connect its land with ocean shipping at Ventura. The producers of California have a great advantage in their proximity to the ocean, which gives them free commerce with the outside world. Crude oil is now sold at $3 per barrel in Los Angeles, and the oil companies are making immense profits. There is a very large amount of oil territory as yet undeveloped, and a rich reward awaits enterprise in these regions. In the Camulos District, which lies west of the San Fernando, are even stronger surface indications of oil than there were in the Pico Canon. We first went up the Brea Canon, in which are numerous outbursts and springs of oil. Ascending the mountain west of this canon, we could plainly see the break in the mountains crossing from the San Fernando through this district to those beyond which have been developed. A couple of miles farther west, the Hooper Canon stretches back over two miles into the mountain, and is full of oil. Great pools of oil fill its water courses, that are dry at present. Hundreds of barrels of oil must be wasted away and evaporated during a year. A well put down only 90 feet by horse power, struck light oil in considerable quantity, and, had it not been for the death of one of the owners and the consequent suspension of operations, would doubtless have yielded in large quantities at the depth of a few hundred feet.

The mountainous territory between these two canons will probably in a few years be the scene of great activity. In the Little Sespe District, a few miles west of Camulos, a 125 barrel well was struck at 1,500 feet recently. The Santa Paula region, a little farther west, is also yielding large profits to the parties developing it.

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NUTRITIVE VALUE OF CONDIMENTS.

By HELEN D. ABBOTT, Assistant in the Chemical Laboratory of the Philadelphia Polyclinic, and College for Graduates in Medicine.

The prevailing opinion respecting the substances known as condiments is, that they possess essentially stimulating qualities, rendering them peculiarly fitted for inducing, by reflex action, the secretion of the alimentary juices. Letheby gives, as the functions of condiments, such as pepper, mustard, spices, pot-herbs, etc., that besides their stimulating properties they give flavor to food; and by them indifferent food is made palatable, and its digestion accelerated. He enumerates as aids to digestion—proper selection of food, according to the taste of the individual, proper treatment of it as regards cooking, and proper variation of it, both as to its nature and treatment.

While it is difficult to give an entirely satisfactory definition as to what constitutes food, the following extracts from standard works will serve as guides. Hermann[1] says: "The compound must be fit for absorption into the blood or chyle, either directly, or after preparation by the processes of digestion, i.e., it must be digestible. It must replace directly some inorganic or organic constituent of the body; or it must undergo conversion into such a constituent, while in the body; or it must serve as an ingredient in the construction of such a constituent." He further says that water, chlorides, and phosphates are the most indispensable articles of diet. Watts[2] states that "whatever is commonly absorbed in a state of health is perhaps the best, or rather the truest, definition of food."

[Footnote 1: Elements of Human Physiology, by L. Hermann. Translated by Gamgee.]

[Footnote 2: Dictionary of Chemistry, vol. iv., pages 147-8.]

Chemical analysis shows that the most important and widely applicable foods contain carbon, hydrogen, oxygen, nitrogen, and mineral matter, the latter containing phosphates and chlorides. Other things being equal, it may be considered that the comparative nutrient value of two articles is in proportion to the amounts of carbon, nitrogen, and phosphoric acid they contain.

"The food of man also contains certain substances known under the name of condiments. Since these bodies perform their functions outside the real body, though within the alimentary canal, they have no better reason to be considered as food than has hunger, optimum condimentum."[1] Such is the positively expressed opinion of Foster, the author of the article on nutrition in Watts' Dictionary of Chemistry. With a view of determining how far the common condiments deserve this summary dismissal, a number of analyses have been made in the laboratory of the Philadelphia Polyclinic. My examinations were especially directed to the mineral matter, phosphoric acid, and nitrogen. The following table shows the result of the analyses:

Percent. Percent. of ash. of P{2}O{5}.

Fennel........................ 9.00 .103 Marjoram...................... 8.84 .050 Peppermint.................... 8.80 .016 Thyme......................... 8.34 .122 Poppy......................... 7.74 .024 Sage.......................... 7.58 .033 Caraway....................... 7.08 .118 Spearmint..................... 7.06 .017 Coriander..................... 6.10 .097 Cloves........................ 5.84 .563 Allspice...................... 5.54 .017 Mustard....................... 3.90 .134 Black pepper.................. 3.60 .011 Jamaica ginger................ 3.16 .052 Cinnamon...................... 3.02 .009 Mace.......................... 2.44 .230 Nutmeg........................ 2.24 .092 Celery........................ 1.29 .082 White pepper.................. 1.16 .017 Aniseed....................... 1.05 .113

[Footnote 1: Ibid., page 149.]

The articles were examined in the condition in which they were obtained in the market, without any preliminary drying, selecting, or preparation. The ash was obtained by burning in a platinum crucible, at as low a temperature as possible, dissolving in hydrochloric acid the phosphoric acid separated as ammonium molybdo-phosphate, and determined in the usual manner.

Qualitative tests made for nitrogen indicated its presence in each one of the condiments examined.

It is of importance to observe that the majority of these condiments are fruits, ripe or nearly so. The seed appropriates to itself the nitrogen and the greatest nutritive properties for the development of the future plant. All nutritive substances fall into two classes: the one serves for the repair of the unoxidizable constituents of the body, the other is destined to replace the oxidizable. Condiments fulfill both of these requirements, as is shown by a study of their composition; the phosphoric acid and nitrogen are taken up by the tissues, as from other substances used in diet. Some articles affect the character of the excretions; this is often due to essential oils; the presence of these in the excretions cannot be said to diminish the value of the substances in supplying the tissues the necessary elements. The same holds true for condiments; the essential oils conspicuous in them are accorded only stimulating properties; however, it may be observed that the essential oils in tea and coffee are accredited with a portion of the dietetic value of these beverages. It appears that when condiments are used in food, especially for the sick, they may serve the double purpose of rendering the food more appetizing and of adding to its nutritive value. The value of food as a purely therapeutic agent is attracting some attention at present, and in its study we must not neglect those substances which combine stimulant and nutritive qualities.—Polyclinic.

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