V = v x (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 deg. 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.

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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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A catalogue, containing brief notices of many important scientific papers heretofore published in the SUPPLEMENT, may be had gratis at this office.

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