Chapter VII: MISCELLANEOUS.--The Missing German Corvette Augusta.--With (4)

As soon as it arrives in a current of heated air, it will ascend, passing along with the current, and descending or rising as the current is either warm or cold. The effect of the cold fresh air from windows or doors, as well as the effect of the radiant heat from the fire, can be thus thoroughly studied. Some of our pet theories may receive a cruel shock from this experiment; but, in the end, the ventilation of the room will doubtless be benefited, if we apply the information obtained. It will be discovered that the wide-throated chimney is the cause of the little black arrows turning their backs on the right path and our theoretical outlets for vitiated air becoming inlets. The chimney flue must have an enormous supply of air, and it simply draws it from the most easily accessible places. From 1,000 to 2,000 cubic feet of air per hour is a large "order" for a small room. Therefore, until we have made ample provision for the air supply to the fire, it is quite useless to attempt to ventilate the upper part of the room, either by ventilating gas lights or one of the cheap ventilators with little talc flappers, opening into the chimney when there is an up draught, and shutting themselves up when there is any tendency to down draught. The success of these and all other ventilators depends upon there being a good supply of air from under the door or through the spaces round the window frames. These fresh air supplies are, of course, unendurable; but if one of the spaces between the joists of the floor is utilized to serve as an air conduit, and made to discharge itself under the fender (raised about two inches for the purpose), quite another state of things will be set up. Then the supply of air thus arranged for will satisfy the fire, without drawing from the doors and windows, and at the same time supply a small quantity of fresh air into the room. But the important fact that the radiant heat from the fire will pass through the cold air without warming it all must not be lost sight of. In reality, radiant heat only warms the furniture and walls of the room or whatever intercepts its rays. The air of the room is warmed by passing over these more or less heated surfaces; and as it is warmed, it rises away to the ceiling. Therefore, if we desire to warm any of this fresh air supplied to the fire, it must be made to pass over a heated surface. The fender may be used for this purpose by filling up the two inch space along the front, as shown in the drawing, with coarse perforated metal. This will also prevent cinders from getting under it. It will be found that for the greater part of the year the chimney ventilator and the supply to the fire will materially prevent "stuffiness," and keep those disagreeable draughts under control, even although the room be lighted with a 3 light chandelier burning a large quantity of gas.

With improvements in gas burners, we may expect to light rooms perfectly with a less expenditure of gas than we now do. But we cannot light a room without in some measure creating heat; and I think I have shown that we want this heat at the ceiling line for the greater part of the year.

In summer we do not use gas for many hours; but, on the other hand, it is more difficult, with an outside temperature at 65° to 70° Fahr., to keep the air in proper movement in small rooms. There are also times in the fall of the year, and also in spring, when the nights are unusually warm; and, with a few friends in our rooms, the lighting becomes a "hot" question, not to say a "burning" one. On these occasions we have to resort to exceptional ventilation, which for ordinary every-day life would be too much. It is then, and on summer nights, that the system of ventilation by diffusion is most useful. To explain it, when two volumes of air of different temperatures or specific gravities find themselves on opposite sides of a screen or other medium, of muslin, cloth, or some more or less porous substance, they diffuse themselves through this medium with varying rapidity, until they become of equal density or temperature. Therefore, if we fill the upper part of a window (which can be opened, downward) with a strained piece of fine muslin or washed common calico, the air in the room, if hotter than the external air, will, when the window is more or less opened, pass out readily into the cooler air, and the cooler air will pass in through the pores of the medium. The hotter air passing out faster than the cooler air will come in, no draught will be experienced; and the window may be opened very widely without any discomfort from it.

It is, of course, quite impossible, in the limits of a paper, to do more than indicate a means of ventilation which will be effective under most circumstances of lighting with those gas burners and fittings usually employed, and which will lend itself readily to modifications which will be necessitated by the use of some of the newest forms of burners and ventilating gas lights.

In conclusion, I wish to draw attention to an important discovery I have made in reference to blackened ceilings, for which, up to the present time, gas has been chiefly blamed. I have long entertained the belief that with a proper burner it is possible to obtain perfect combustion, without any smoke; and a series of experiments with white porcelain plates hung over some burners used in my own house proved conclusively that the discoloration which spread itself all over my whitewashed ceilings arose from the state of the atmosphere, which in all large towns is largely mixed with heavy smoky particles, and from the dust or dirt created in rooms by the use of coal fires as well as from the smoke which, more frequently than one is at first supposed to imagine, escapes from the fire-place into the room. I therefore, in two of my best rooms, which required to have the ceilings whitened every year, substituted varnished paper ceilings (light oak paper, simply put on in the usual way, and varnished) instead of whitewash. I also changed the coal fires for gas fires. These alterations have gone through the test of two winters, and the ceilings are now as clean as when they were first done. The burners have been used every night, and the gas fires every day, during the two winters. No alteration has been made in the burners employed, and no "consumers" have been used over them. If the varnished paper ceilings are tried, I am sure that every one will like them better than the time honored dirty whitewash, which is simply a fine sieve. This fact is clearly shown by the appearance of the rafters, which, after a short time, invariably show themselves whiter than the spaces between.

* * * * *

ANDERS' TELEPHONE.

Mr. G.L. Anders' telephone, shown in the accompanying cut, combines in a single apparatus a transmitter, A, a receiver, B, and a pile, C. The transmitter consists of a felt disk, a, containing several large apertures, and fixed by an insulating ring, c, to a metallic disk, d, situated within the box, D. The apertures, b, are filled with powdered carbon, e, and are covered by a thin metal plate, f, which is fixed to the insulating ring, c, by means of a metallic washer, g. Back of the transmitter is arranged the receiver, B, which consists of an ordinary electro-magnet with a disk in front of its poles. The pile, C, placed behind the receiver, consists of a piece of carbon, h, held by a partition, i, and covered with a salt of mercury, and of a plate of zinc, l, which is held at a distance from the mercurial salt by a spring, m, fixed to the insulating piece, n.

When the button, o, which is a poor conductor, is pressed, the zinc plate, l, comes into contact with the mercurial salt, and the circuit is closed through the line wire 1, the pile, the receiver, the transmitter, and the line wire 2, while when the button is freed the current no longer passes. The apparatus, then, can serve as a receiver or transmitter only when the button is pressed.--_Bull. de la Musee de l'Industrie_.

* * * * *

BROWN'S ELECTRIC SPEED REGULATOR.

When the sea is rough, and the screw leaves the water as a consequence of the ship's motions, the rotary velocity of the screw and engine increases to a dangerous degree, because the resistance that the screw was meeting in the water suddenly disappears. When the screw enters the water again, the resistance makes itself abruptly felt, and causes powerful shocks, which put both the screw and engine in danger. Ordinary regulators are powerless to overcome this trouble, since their construction is such that they act upon the engine only when the excess of velocity has already been reached.

Several remedies have been proposed for this danger. For example, use has been made of a float placed in a channel at the side of the screw, and which closes the moderator valve by mechanical means or by electricity when the screw descends too low or rises too high.

Mr. Brown's system is based upon a new idea. The apparatus (see figure) consists of two contacts connected by an electric circuit. One of them, b, is fixed to the ship in such a way as to be constantly in the water, while the other, a, corresponds to the position above which the screw cannot rise without taking on a dangerous velocity. In the normal situation of the ship, the electric circuit, c (in which circulates a current produced by a dynamo, d), is closed through the intermedium of the water, which establishes a connection between the two contacts. When the contact, a, rises out of the water, the current is interrupted. The electro, d, then frees its armature, f, and the latter is pulled back by a spring--a motion that sets in action a small steam engine that closes the moderator valve. When the contact, a, is again immersed, the electro, e, attracts its armature, and thus brings the moderator valve back to its normal position. It is clear that the contact, a, must be insulated from the ship's side.

Several contacts, a, might be advantageously arranged one above another, in order to close the moderator valve more or less, according to the extent of the screw's rise or fall.

* * * * *

MAGNETO-ELECTRIC CROSSING SIGNAL.

We illustrate to-day a new application of electricity to railroad crossing signaling which the Pennsylvania Steel Company, of Steelton, Pa., has just perfected. By its operation an isolated highway crossing in the woods or any lonely place can be made perfectly safe, and that, too, without the expense of gates and a man to work them or of a flagman. It is surely a great improvement over the old methods, and it is likely to have a large sale. In addition to considerations of safety, possible saving in salaries to railroad companies by its use will be great. This device is more reliable than a human being, and can make any crossing safe to which it is applied. Its operation is described as follows:

The illustration shows the device as used on a single track railroad, where it is so arranged as to be operated only by trains approaching the crossing (i.e., in the form illustrated, from the right). A similar box on the other side of the crossing is used for trains approaching in the other direction. Two plates connected by a link, and pivoted, are placed alongside of one rail, close enough to it to be depressed by the treads of the wheels. By another link, one of the plates called the rock plate (the one to the right) is connected to a rock shaft which extends through a strong bearing into the heavy iron case or box shown, at a suitable distance from the rail, within which an electric generator is placed; the whole being mounted and secured upon the ends of two long ties framed to receive it.

The action of this rock plate is peculiar. It is pivoted at the rear end, not to a fixed point, but to a short crank arm, the bearing for which is inclosed in the small box shown. As the first wheel of a train which is approaching in the desired direction (from the right in the engraving) touches it, it will be seen that it must not only depress it, but produce a slight forward motion, causing a corresponding rotary motion in the rock shaft which actuates the apparatus. On the other hand, when a train is approaching from the other direction, or has already passed the crossing, its wheels strike first the curved plate to the left of the illustration, and by means of the peculiar link connections shown, depress the rock plate so as to clear the wheels before the wheels touch it, but the depression is directly vertical, so that it does not give any horizontal motion to it, which would have the effect of actuating the rock shaft. Consequently, trains pass over the apparatus in one direction without having any effect upon it whatever, the different point at which the same force is applied to the rock plate giving the latter an entirely different motion.

The slight rotary motion which is in this way communicated to the rock shaft, when a train is approaching in the right direction, compresses a spring inside the case. As each wheel passes off the rock plate, the reaction of the spring throws it up again to its former position, giving additional speed to the gearing within, which is set in motion at the passage of the first wheel, and operates the electric "generator." The spring is really the motive power of the alarm. A small but heavy fly-wheel is connected with the apparatus, the top of which is just visible in the engraving, which serves to store up power to run the "generator," which is nothing more than a small dynamo, for the necessary number of seconds after the rear of the train has passed. The dynamo dispenses with all need for batteries, and reduces the work of maintenance to occasionally refilling the oil-cups and noticing if any part has been broken.

A suitable wire circuit is provided, commencing at the generator with insulated and protected wire, and continued with ordinary telegraph wire, which can be strung on telegraph poles or trees leading to the electric gong, Fig. 2, which rings as long as the armature revolves. It is a simple matter so to proportion the mechanism for the required distance and speed that the revolutions of the armature and the ringing of the gong shall continue until the train reaches the crossing; and as each wheel acts upon the apparatus, the more wheels there are in the train the longer the bell will ring, a very convenient property, since the slowest trains have nearly always the most wheels. The practical limits to the ringing of the gong are that it will stop sounding after the head of the train has passed the crossing and before or very soon after the rear has passed. A "wild" engine running very slowly might not actuate the signal as long as was desirable, but even then it is not unreasonably claimed the warning would probably last long enough for all practical requirements, as a team approaching a crossing at eight miles per hour takes 42 seconds to go 500 feet. All the bearings of any importance are self-lubricated by oil cups, the whole apparatus being designed to require inspection not more than once a month. The iron case when shut is water-tight, and when duly locked cannot be maliciously tampered with without breaking open the case; so that, the manufacturers claim, it will not be essential to examine it more than once a month. The parts outside the case are all strong and heavy, and not likely to get out of order, while easily inspected.

The apparatus can be used for announcing trains as well as sounding alarms, as the gongs can be placed upon any post or building. The gong has a heavy striker, and makes a great deal of noise, so that no one should fail to hear it.--_Railway Review_.

* * * * *

THE SIZES OF BLOOD CORPUSCLES.

Professor Theodore G. Wormley, in the new edition of his work, gives the following sizes of blood corpuscles, as measured by himself and Professor Gulliver. We have only copied the sizes for mammals and birds. It will be seen that, with three or four exceptions, the sizes obtained by the two observers are practically the same:

Mammals Wormley. Gulliver.

Man 1-3250 1-3260
Monkey 1-3382 1-3412
Opossum 1-3145 1-3557
Guinea pig 1-3223 1-3538
Kangaroo 1-3410 1-3440
Muskrat 1-3282 1-3550
Dog 1-3561 1-3532
Rabbit 1-3653 1-3607
Rat 1-3652 1-3754
Mouse 1-3743 1-3814
Pig 1-4268 1-4230
Ox 1-4219 1-4267
Horse 1-4243 1-4600
Cat 1-4372 1-4404
Elk 1-4384 1-3938
Buffalo 1-4351 1-4586
Wolf (prairie) 1-3422 1-3600
Bear (black) 1-3656 1-3693
Hyena 1-3644 1-3735
Squirrel (red) 1-4140 1-4000
Raccoon 1-4084 1-3950
Elephant 1-2738 1-2745
Leopard 1-4390 1-4319
Hippopotamus 1-3560 1-3429
Rhinoceros 1-3649 1-3765
Tapir 1-4175 1-4000
Lion 1-4143 1-4322
Ocelot 1-3885 1-4220
Mule 1-3760
Ass 1-3620 1-4000
Ground squirrel 1-4200
Bat 1-3966 1-4173
Sheep 1-4912 1-5300
Ibex 1-6445
Goat 1-6189 1-6366
Sloth 1-2865
Platypus (duck-billed) 1-3000
Whale 1-3099
Capybara 1-3164 1-3190
Seal 1-3281
Woodchuck 1-3484
Muskdeer 1-12325
Beaver 1-3325
Porcupine 1-3369
Llama, Long diam. 1-3201 1-3361
Short " 1-6408 1-6229
Camel, Long diam. 1-3331 1-3123
Short " 1-5280 1-5876

WORMLEY GULLIVER.
Birds. Length. Breadth. Length. Breadth.

Chicken 1-2080 1-3483 1-2102 1-3466
Turkey 1-1894 1-3444 1-2045 1-3599
Duck 1-1955 1-3504 1-1937 1-3424
Pigeon 1-1892 1-3804 1-1973 1-3643
Goose 1836 1-3839
Quail 2347 1-3470
Dove 2005 1-3369
Sparrow 2140 1-3500
Owl 1736 1-4076

The subject of minute measurements was discussed in an interesting manner in an address before the Microscopical Section of the A.A.A.S. last year, an abstract of which was published in this journal, vol. v., p. 181.

The slight differences in size accurately given in this table are not always appreciable under modern amplification, but under a power of 1,150 diameters "corpuscles differing by the 1-100000 of an inch are readily discriminated." For the conclusions of Prof. Wormley as regards the possibility of identifying blood of different animals, the reader is referred to his book on Micro-Chemistry of Poisons.--_Amer. Micro. Jour._

* * * * *

THE ABSORPTION OF PETROLEUM OINTMENT AND LARD BY THE SKIN.

[Footnote: From the _American Druggist_.]

E. Joerss has investigated the question whether ointments made with vaseline or other petroleum ointments are really as difficult of resorption by the skin, or of yielding their medicinal ingredients to the latter, as has been asserted. In solving this question, he considered himself justified in drawing conclusions from the manner in which such compounds behaved toward _dead_ animal membrane. If any kind of osmosis could take place, he argued, from ointments prepared with vaseline, etc., through dead membranes, such osmosis would most probably also take place through living membranes. At all events, the endosmotic or exosmotic action of the skin of a living body must necessarily play an important _role_ in the absorption of medicinal agents; and, on the other hand, it is plain that fats, which render the living skin impermeable, necessarily also diminish or entirely neutralize its osmotic action. To test this, the author made the following experiments:

Bladder was tied over the necks of three wide-mouthed vials, with bottoms cut off, and each was filled with iodide of potassium ointment.

No. 1 contained an ointment made with lard.

No. 2, one made with unguentum paraffini (_Germ. Pharm_.), and

No. 3, one made with unguentum paraffini mixed with 3 per cent. of lard.

All three vials were then suspended in beakers filled with water. After standing twenty-four hours at the ordinary temperature, the contents of none of the beakers gave any iodine reaction. After having been placed into a warm temperature, between 25-37° C., all three showed iodine reactions after three hours, Nos. 2 and 3 very strongly, No. 1 (with lard alone) very faintly.

The same experiment was now repeated, with the precaution that the bladder was previously washed completely free from chlorine. Each vial was suspended, at a temperature of 25-27° C., in 50 grammes of distilled water. After three hours, the contents of No. 1 (containing the ointment made with _lard_) gave _no_ iodine reaction; the contents of the other two, however, gave traces. After eight hours no further change had taken place. The temperature was now raised to 30-35° C., and kept so for eight hours. All three beakers now gave a strong iodine reaction, 0.2 c.c. of normal silver solution being required for each 15 grammes of the contents of the beakers.

In addition to the iodide, some of the fatty base had osmosed through the membrane in each case.

The next experiment was made by substituting a piece of the skin (freed from chlorine by washing) of a freshly killed sheep for the bladder. The ointment in No. 3 in this case was made with 10 per cent. of lard. No reaction was obtained, at the ordinary temperature, after twelve hours, nor after eight more hours, at a temperature of 25-30° C. After letting them stand for eight hours longer at 30-37° C., a faint reaction was obtained in the case of the ointment made with unguentum paraffini; a still fainter with No. 3; but no reaction at all with No. 1 (that made with lard). None of the fats passed through by osmosis. After eight hours more, the iodine reaction was quite decisive in all cases, but no fat had passed through even now. On titrating 20 grammes of the contents of each beaker,

No. 1 required 0.5 c.c. of silver solution.
No. 3 " 0.5 c.c. "
No. 2 " 0.7 c.c. "

showing that the most iodine had osmosed in the case of the ointment made with unguentum paraffini (equivalent to vaseline).

* * * * *

THE TAILS OF COMETS.

I.--If we throw a stone into the water, a wave will be produced that will extend in a circle. The size of this wave and the velocity with which it extends depend upon the size of the stone, that is to say, upon the intensity of the mechanical action that created it. The extent and depth of the water are likewise factors.

If we cause a cord to vibrate in the water, we shall obtain a succession of waves, the velocity and size of which will be derived from the cord's size and the intensity of its action. These waves, which are visible upon the surface, constitute what I shall call _mechanical waves_. But there will be created at the same time other waves, whose velocity of propagation will be much greater than that of the mechanical ones, and apparently independent of mechanical intensity. These are _acoustic waves_. Finally, there will doubtless be created _optical waves_, whose velocity will exceed that of the acoustic ones. That is to say, if a person fell into water from a great height, and all his senses were sufficiently acute, he would first perceive a luminous sensation when the first optical wave reached him, then he would perceive the sound produced, and later still he would feel, through a slight tremor, the mechanical wave.[1]

[Footnote 1: Certain persons, as well known, undergo an optical impression under the action of certain sounds.]

Under the action of the same mechanical energy there form, then, in a mass of fluid, waves that vary in nature, intensity, and velocity of propagation; and although but three modes appreciable to our senses have been cited, it does not follow that these are the only ones possible.

We may remark, again, that if we produce a single wave upon water, it will be propagated in a uniform motion, and will form in front of it successive waves whose velocity of propagation is accelerated.

This may explain why sounds perceived at great distances are briefer than at small ones. A detonation that gives a quick dead sound at a few yards is of much longer duration, and softer at a great distance.

The laws that govern the system of wave propagation are, then, very complex.

II.--If an obstacle be in the way of the waves, there will occur in each of them an _alteration_, a break, which it will carry along with it to a greater or less distance. This succession of alterations forms a trace behind the obstacle, and in opposition to the line of the centers. Finally, if the obstacle itself emits waves in space that are of less intensity then those which meet it, these little waves will extend in the wake of the large ones, and will form a trace of parabolic form situated upon the line of the centers.

III.--Let us admit, then, that the sun, through the peculiar energy that develops upon its surface or in its atmosphere, engenders in ethereal space successive waves of varying nature and intensity, as has been said above, and let us admit that its _mechanical_ waves are traversed obliquely (Fig. 1) by any spherical body--by a comet, for example; then, under the excitation of the waves that it is traversing, and through its velocity, the comet will itself enter into action, and produce mechanical waves in its turn. As the trace produced in the solar waves consists of an agitation of the ether on such trace, it will become apparent, if we admit that every luminous effect is produced by an excitation--a setting of the ether in vibration. The mechanical waves engender of themselves, then, an emission of optical waves that render perceptible the alteration which they create in each other.

Let a be the position of the comet. The altered wave, a, will carry along the mark of such alteration in the direction a b, while at the same time extending transversely the waves emitted by the comet. During this time the comet will advance to a', and the wave will be altered in its turn, and carry such alteration in the direction, a' b'.

The succession of all these alterations will be found, then, upon a curve a'' d' d, whose first elements, on coming from the comet, will be upon the resultant of the comet's velocity, and of the propagation of the solar waves. Consequently, the slower the motion of the comet, with respect to the velocity of the solar waves, the closer will such resultant approach the line of centers, and the more rectilinear will appear the trace or tail of the comet.

IV.--If the comet have satellites, we shall see, according to the relative position of these, several tails appear, and these will seem to form at different epochs. If c and s be the positions of a comet and a satellite, it will be seen that if, while the comet is proceeding to c', the satellite, through its revolution around it, goes to s', the traces formed at c and s will be extended to d and d', and that we shall have two tails, c' d and s' d', which will be separated at d and d' and seem to be confounded toward c' s'.

V.--When the comet recedes from the sun, the same effect will occur--the tail will precede it, and will be so much the more in a line with the sun in proportion as the velocity of the solar waves exceeds that of the comet.

If we draw a complete diagram (Fig. 4), and admit that the alteration of the solar waves persists indefinitely, we shall see (supposing the phenomenon to begin at a) that when the comet is at a 1, the tail will and be at a 1 b; when it is a 2 the tail will be at a 2 b'; and when it is at a 4, the tail will have become an immense spiral, a 4 b'''. As in reality the trace is extinguished in space, we never see but the origin of it, which is the part of it that is constantly new--that is to say, the part represented in the spirals of Fig. 4.

The comet of 1843 crossed the perihelion with a velocity of 50 leagues per second; it would have only required the velocity of the solar waves' propagation to have been 500 leagues per second to have put the tail in a sensibly direct opposition with the sun.

Knowing the angle [gamma] (Fig. 5) that the tangent to the orbit makes with the sun at a given point, and the angle [delta] of the track upon such tangent, as well as the velocity v of the comet, we can deduce therefrom the velocity V of the solar waves by the simple expression:

V = v × (sinus [delta] / sinus([gamma] - [delta])) or (Fig. 1),

V = da/t'',

t'' being the time taken to pass over aa''.

VI.--The tail, then, is not a special matter which is transported in space with the comet, but a disturbance in the solar waves, just as sound is an atmospheric disturbance which is propagated with the velocity of the sonorous wave, although the air is not transported. The tail which we see in one position, then, is not that which we see in another; it is constantly renewed. Consequently, it is easy to conceive how, in as brief a time as it took the comet of 1843 to make a half revolution round the sun, the tail which extended to so great a distance appeared to sweep the 180° of space, while at the same time remaining in opposition to the great luminary.

The spiral under consideration may be represented practically. If to a vertical pipe we adapt a horizontal one that revolves with a certain velocity, and throws out water horizontally, it will be understood that, from a bird's eye view, the jet will form a spiral. Each drop of water will recede radially in space, the spiral will keep forming at the jet, and if, through any reason, the latter alone be visible, we shall see a nearly rectilinear jet that will seem to revolve with the pipe.

Finally, if the jet be made to describe a curve, m n (Fig. 4), while it is kept directed toward the opposite of a point, c, the projected water will mark the spiral indicated, and this will continue to widen, and each drop will recede in the direction shown by the arrows.

VII.--It seems to result from this explanation that all the planets and their satellites ought to produce identical effects, and have the appearance of comets. In order to change the conditions, it suffices to admit that the ethereal mass revolves in space around the sun with a velocity which is in each place that of the planets there; and this is very reasonable if, admitting the nebular hypothesis, we draw the deduction that the cause that has communicated the velocity to the successive rings has communicated it to the ethereal mass.

The planets, then, have no appreciable, relative velocity in space, and for this reason do not produce mechanical waves; and, if they become capable of doing so through a peculiar energy developed at their surface, as in the case of the sun, they are still too weak to give very perceptible effects. The satellites, likewise, have relatively too feeble velocities.

The comet, on the contrary, directly penetrates the solar waves, and sometimes has a relatively great velocity in space. If its proper velocity be of directly opposite direction to that of the ethereal mass's rotation, it will then be capable of producing sufficiently intense mechanical effects to affect our vision.

VIII.--Finally, seeing the slight distances at which these stars pass the sun, the attraction upon the comet and its satellites may be very different, and the velocity of rotation of the latter, being added to or deducted from that of the forward motion, there may occur (as in the case shown in Fig. 6) a separation of a satellite from the principal star. The comet then appears to separate into two, and each part follows different routes in space; or, as in Fig. 7, one of the satellites may either fall into the sun or pursue an elliptical orbit and become periodical, while the principal star may preserve a parabolic orbit, and make but one appearance.--_A. Goupil._

* * * * *

THE DOUBLE ROLE OF THE STING OF THE HONEY BEE.

[Footnote: Translated from an article entitled "Ueber eine doppelrolle des stachels der honigbienen" in _Deutschamerikanische Apotheker Zeitung_, 15 Jan., 1885, Jahrg. 5, p. 664; there reprinted from _Ind. Blatter_.]

Very important and highly interesting discoveries have recently been made in regard to a double role played by the sting of the honey bee. These discoveries explain some hitherto inexplicable phenomena in the domestic economy of the ants. It is already known that the honey of our honey bees, when mixed with a tincture of litmus, shows a distinct red color, or, in other words, has an acid reaction. It manifests this peculiarity because of the volatile formic acid which it contains. This admixed acid confers upon crude honey its preservative power. Honey which is purified by treatment with water under heat, or the so-called honey-sirup, spoils sooner, because the formic acid is volatilized. The honey of vicious swarms of bees is characterized by a tart taste and a pungent odor. This effect is produced by the formic acid, which is present in excess in the honey. Hitherto it has been entirely unknown in what way the substratum of this peculiarity of honey, the formic acid in the honey, could enter into this vomit from the honey stomach of the workers. Only the most recent investigations have furnished us an explanation of this process. The sting of the bees is used not only for defense, but quite principally serves the important purpose of contributing to the stored honey an antizymotic and antiseptic substance.

The observation has recently been made that the bees in the hive, even when they are undisturbed, wipe off on the combs the minute drops of bee poison (formic acid) which from time to time exude from the tip of their sting. And this excellent preservative medium is thus sooner or later contributed to the stored honey. The more excitable and the more ready to sting the bees are, the greater will be the quantity of formic acid which is added to the honey, and the admixture of which good honey needs. The praise which is so commonly lavished upon the Ligurian race of our honey bees, which is indisposed to sting--and such praise is still expressed at the peripatetic gatherings of German bee-masters--is therefore from a practical point of view a false praise. Now we understand also why the stingless honey bees of South America collect little honey. It is well known that never more than a very small store of honey is found in felled trees inhabited by stingless _Melipona_. What should induce the _Melipona_ to accumulate stores which they could not preserve? They lack formic acid. Only three of the eighteen different known species of honey bees of northern Brazil have a sting. A peculiar phenomenon in the life of certain ants has always been problematical, but now it finds also its least forced explanation. It is well known that there are different grain-gathering species of ants. The seeds of grasses and other plants are often preserved for years in their little magazines, without germinating. A very small red ant, which drags grains of wheat and oats into its dwellings, lives in India. These ants are so small that eight or twelve of them have to drag on one grain with the greatest exertion. They travel in two separate ranks over smooth or rough ground, just as it comes, and even up and down steps, at the same regular pace. They have often to travel with their booty more than a thousand meters, to reach their communal storehouse. The renowned investigator Moggridge repeatedly observed that when the ants were prevented from reaching their magazines of grain, the seeds begun to sprout. The same was the case in abandoned magazines of grain. Hence the ants know how to prevent the sprouting of the grains, but the capacity for sprouting is not destroyed. The renowned English investigator John Lubbock, who communicates this and similar facts in his work entitled "Ants, Bees, and Wasps," adds that it is not yet known in what way the ants prevent the sprouting of the collected grains. But now it is demonstrated that here also it is only the formic acid, whose preservative influence goes so far that it can make seed incapable of germination for a determinate time or continuously.

It may be mentioned that we have also among us a species of ant which lives on seeds, and stores these up. This is our _Lasius niger_, which carries seeds of _Viola_ into its nests, and, as Wittmack has communicated recently to the Sitzungsberichte der gesellschaft naturforschender freunde zu Berlin, does the same with the seeds of _Veronica hederaefolia_.

Syke states in his account of an Indian ant, _Pheidole providens_, that this species collects a great store of grass-seeds. But he observed that the ants brought their store of grain into the open air to dry it after the monsoon storms. From this it appears that the preservative effect of the formic acid is destroyed by great moisture, and hence this drying process. So that among the bees the honey which is stored for winter use, and among the ants the stores of grain which serve for food, are preserved by one and the same fluid, formic acid.

EDITORIAL NOTE.

This same theory has been suggested many times by our most advanced American bee-keepers. It has been hinted that this same formic acid was what made honey a poison to many people, and that the sharp sting of some honey, notably that from bass wood or linden, originated in this acid from the poison sac. If this is the correct explanation, it seems strange that the same kind of honey is always peculiar for greater or less acidity as the case may be. We often see bees with sting extended and tipped with a tiny drop of poison; but how do we know that this poison is certainly mingled with the honey? Is this any more than a guess?--_A.J. Cook, in Psyche_.

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CHLORIDES IN RAINFALL OF 1884.

We are apt to regard the rain solely as a product of distillation, and, as such, very pure. A little reflection and a very slight amount of experimental examination will quickly disabuse those who have this mistaken and popular impression of their error. A great number of bodies which arise from industrial processes, domestic combustion of coal, natural changes in vegetable and animal matter, terrestrial disturbances as tornadoes and volcanic eruptions, vital exhalations, etc., are discharged into the atmosphere, and, whether by solution or mechanical contact, descend to the surface of the earth in the rain, leaving upon its evaporation in many instances the most incontestable evidences of their presence. The acid precipitation around alkali and sulphuric acid works is well known; the acid character of rains collected near and in cities, and the remarkable ammoniacal strength of some local rainfalls, have been fully discussed. The exhaustive experiments of Dr. Angus Smith in Scotland, and the interesting reports of French examiners, have made the scientific world familiar, not only qualitatively but quantitatively, with the chemical nature of some rains, as well as with their solid sedimentary contents.

Some years ago my attention was unpleasantly drawn to the fact that the rain water in our use reacted for chlorine; and on finding this due solely to the washing out from the atmosphere of suspended particles of chloride of sodium or other chlorides or free chlorine, it appeared interesting to determine the average amount of these salts in the rain water of the sea coast. The results given in this paper refer to a district on Staten Island, New York harbor, at a point four miles from the ocean, slightly sheltered from the ocean's immediate influence by the intervention of low ranges of hills. They were communicated to the Natural Science Association of Staten Island, but the details of the observations may prove of interest to the readers of the _Quarterly_, and may there serve as a record more widely accessible.

It has long been recognized that the source of chlorine in rainfalls near the sea was the sea itself, the amount of chlorides, putting aside local exceptions arising from cities or manufactories, increasing with the proximity of the point of observation to the ocean, and also showing a marked relation to the exposure of the position chosen to violent storms. Thus the west coast rainfalls of Ireland contain larger quantities of chlorides than those of the east, and the table given by Dr. Smith shows the variations in neighboring localities on the same seafront. The chlorides of the English rains diminish as the observer leaves the sea coast. In the following observations the waters of thirty-two rains were collected, the chlorine determined by nitrate of silver in amounts of the water varying from one liter to one-half a liter, and in some instances less. While it is likely that some of the chlorine was due to the presence of chlorides other than common salt, as the position of the point of observation is not removed more than a mile from oil distilleries and smelting and sulphuric acid works in New Jersey, yet this could not even generally have been so, as the rain storms came, for the greater number of instances, from the east, in an opposite direction to the position of the factories alluded to. It has also been noticed by Mr. A. Hollick, to whom these observations were of interest, that in heavy storms a salt film often forms upon fruit exposed to the easterly gales upon the shores of the island.

The yearly average for chlorine is 0.228 grain per gallon; for sodic chloride, 0.376 grain. The total rainfall in our region for 1884, as reported by Dr. Draper at Central Park, was 52.25 inches, somewhat higher than usual, as the average for a series of years before gives 46 inches; but taking these former figures, we find that for that year (1884) each acre of ground received, accepting the results obtained by my examination, 76.24 avoirdupois pounds of common salt, if we regard the entire chlorine contents of the rains as due to that body, or 46.23 pounds of chlorine alone.

In comparison with this result, we find that at Caen, in France, an examination of the saline ingredients of the rain gave for one year about 85 pounds of mineral matter per acre, of which 40 pounds were regarded as common salt.

Although chlorine is almost constantly present in plant tissues, it is not indispensable for most plants, and for those assimilating it in small amounts, our rainfall would seem to offer an ample supply. These facts open our eyes to the possible fertilizing influence of rains, and they also suggest to what extent rains may exert a corrosive action when they descend charged with acid vapors.--_L.P. Gratacap, in School of Mines Quarterly_.

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THE CHROMATOSCOPE.

Some time ago Mr. J.D. Hardy devised an instrument, which he has named a chromatoscope, so easily made by any one who has a spot lens that we take the following description from the _Journal_ of the Royal Microscopical Society: "Its chief purpose is that of illuminating and defining objects which are nonpolarizable, in a similar manner to that in which the polariscope defines polarizable objects. It can also be applied to many polarizable objects. This quality, combined with the transmission of a greater amount of light than is obtainable by the polariscope, renders objects thus seen much more effective. It is constructed as follows: Into the tube of the spot lens a short tube is made to move freely and easily. This inner tube has a double flange, the outer one, which is milled, for rotating, and the inner one for carrying a glass plate. This plate is made of flat, clear glass, and upon it are cemented by a very small quantity of balsam three pieces of colored (stained) glass, blue, red, and green, in the proportion of about 8, 5, and 3. The light from the lamp is allowed to pass to some extent through the interspaces, and is by comparison a strong yellow, thus giving four principal colors. Secondary colors are formed by a combination of the rays in passing through the spot lens.

"The stained glass should be as rich in color and as good in quality as possible, and a better effect is obtained by three pieces of stained glass than by a number of small pieces. The application of the chromatoscope is almost unlimited, as it can be used with all objectives up to the 1/8. Transparent objects, particularly crystals which will not polarize, diatoms, infusoria, palates of mollusks, etc., can not only be seen to greater advantage, but their parts can be more easily studied. As its cost is merely nominal, it can be applied to every instrument, large or small; and when its merits and its utility by practice are known, I am confident that it will be considered a valuable accessory to the microscope."

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Prof. W.O. Atwater, as the results of a series of experiments, finds, contrary to the general opinion of chemists, that plants assimilate nitrogen from the atmosphere. They take up the greatest quantity when supplied with abundant nourishment from the soil. Well fed plants acquired fully one-half their total nitrogen from the air. It seems probable that the free nitrogen of the air is in some way assimilated by the plants.

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