inexorable laws of supply and demand, while giving more than due wages to some of the working class, plunge others into dire distress, which in time saps their strength, both physically and mentally, and ultimately makes them denizens of the mad-house.

Movements in Droseras.

FOR the following account of these movements we are indebted to Alfred W. Bennett: It should be noted, in the first place, that the so-called hairs of the Drosera are true glands; they are an integral part of the leaf itself, and are penetrated by fibrous vessels. They terminate in a pellucid knob, within which their peculiar viscid secretion is found. This has probably an attraction for flies and other small insects, as, if the plant is examined in its native bogs, scarcely a leaf will be found in which an insect is not imprisoned. The experiment was made of placing a very small insect on a leaf beneath a low power of the microscope. The contact of the insect appeared to excite a stronger flow of the secretion, which soon enveloped the body of the animal in a dense, almost transparent, slime, firmly gluing down the wings, and rendering escape hopeless. It still, however, continued its struggles, a motion of the legs being still clearly perceptible after the lapse of three hours. During all this time the insect was sinking lower down towards the surface of the leaf, but only a slight change had taken place in the position of the glands themselves, which had slightly converged so as to imprison it more completely. But after the struggles of the prisoner had ceased, a remarkable change took place in the leaf. Almost the whole of the glands on its surface and its margin, even those removed from the body of the insect by a distance of at least double its own length, began to bend over, and point the knobs at their extremities towards it, though it was not observed that this was accompanied by any increased flow of the secretion from them. The experiment was made in the evening, and by the next morning almost every gland of the leaf was pointing towards the object in the center, forming a dense mass over it.

In a second experiment, a small piece of raw meat was placed on another leaf similar to the first. No immediate change was observable, and no increased flow of secretion; but after the lapse of a few hours a perceptible inclination of the more distant glands towards the object took place. The next morning the piece of meat was found like the fly, sunk down upon the surface of the leaf, with almost the whole of the glands converging towards it, and above it in just the same manner. The changes here were, therefore, perfectly of the same kind as in the case of the fly, though apparently somewhat slower. After the lapse of twenty-four hours the piece of meat appeared decidedly lighter in color; but an accident prevented the process of digestion being further traced. On other leaves pieces of wood and worsted were placed, but in neither of these in

stances was there the least perceptible movement, even after the lapse of considerable periods of time. The organized structures of the fly and of the piece of raw meat, therefore, possessed the power of exciting these movements which the other substances could not provoke.

Consumption of Fuel in Engines.

At the annual meeting of the Institute of Mechanical Engineers in 1863, a careful inquiry was made into the consumption of fuel by the best engines in the Atlantic steam service. The result showed that in no case did it fall below four and a half pounds per horse-power, per hour. Last year they assembled again with the same object in view, and Mr. Bramwell produced a table showing that the average consumption by 17 good examples of compound expansive engines, did not exceed two and a quarter pounds per horse-power, per hour. Mr. E. A. Cowper has proved a consumption not exceeding one and a half pounds per horse-power, per hour, in a compound marine engine, constructed with an intermediate superheating vessel, in accordance with his plans; nor are we likely to stop long at this point of comparative excellence, for it has been shown that theoretical perfection is only to be reached by the combustion of one quarter of a pound of ordinary steam coal. (Dr. Siemens.)

Spectra of Compounds.

MR. J. N. LOCKREY arrives at the following conclusion regarding this subject: Ist. A compound body has as definite a spectrum as a simple one; but while the spectrum of the latter consists of lines, the number and thickness of some of which increase with molecular approach, the spectrum of a compound consists in the main of channeled spaces and bands, which increase in like manner. In short, the molecules of a simple body and of a compound one are affected in the same manner by their approach or recess, so far as their spectra are concerned; in other words, both spectra have their long and short lines or bands. In each case the greatest simplicity of the spectrum depends upon the greatest separation of molecules, and the greatest complexity (a continuous spectrum) upon their nearest approach.

2d. The heat required to act upon a compound, so as to render its spectrum visible, dissociates the compound according to its volatility; the number of true metallic lines which thus appear is a measure of the dissociation; and, doubtless, as the metal lines increase in number the compound bands shine

out.

Liquefaction of Gases.

M. MELLENS states that absorption of chlorine by wood charcoal may go on until it represents a weight of chlorine equal to that of the charcoal. If charcoal thus saturated with chlorine is placed in

one limb of a V-shaped tube, and the extremities thereof sealed, the application of boiling water to the limb containing the charcoal, will cause the chlorine to be volatilized when, under the pressure produced, the gas may be forced to assume the liquid state in the other limb by dipping it in a freezing mixture. By this method chlorine, ammonia, sulphurous, hydro-sulphuric, and hydro-bromic acids, chloride of ethyle and cyanogen have been obtained in the liquid state.

Effects of Worry.

A WRITER in Chambers' Journal says: That the effects of worry are more to be dreaded than those of simple hard work, is evident from noting the class of persons who suffer most from the effects of mental overstrain. The case-book of the physician shows that it is the speculator, the betting man, the railway manager, the great merchant, the superintendent of large manufacturing or commercial works, who most frequently exhibit the symptoms of cerebral exhaustion. Mental cares accompanied by suppressed emotion, occupations liable to great vicissitudes of fortune, and those which involve the bearing on the mind of a multiplicity of intricate details, eventually break down the lives of the strongest. In estimating what may be called the staying powers of different minds under hard work, it is always necessary to take early training into account. A young man, cast suddenly into a position involving great care and responsibility, will break down; whereas, had he been gradually habituated to this position, he would have performed its duties without difficulty. It is probably for this reason that the professional classes generally suffer less from the effects of overstrain than others. They have had a long course of preliminary training, and their work comes on them by degrees; therefore, when it does come in excessive quantity it finds them prepared for it. Those, on the other hand, who suddenly vault into a position requiring severe mental toil generally die before their time.

Memoranda.

A SERIES of experiments made by Professor Ville, in France, show that the diseases that attack the potato are in part the result of a deficiency in the supply of potash in the soil. For five years in succession the Professor planted potatoes in the same soil without any fertilizer; to other plots of ground he added fertilizers that did not contain potash. In all these cases the fruit became diseased in the month of May, while on the other plots where potash❘ was supplied in sufficient quantity, the plants were healthy and yielded an excellent product.

The absolute absence of any atmosphere on the moon has never yet been demonstrated, but only the fact that it does not exceed certain limits, generally

supposed to be much more restricted than is actutally the case. (E. Neison.)

Regarding the use of electricity in the treatment of skin diseases, Beard and Rockwell say: "During the past two years we have treated a number of cases of eczema, acne and prurigo, by central galvanization alone, without making any application whatever to the diseased surface; and under this method of treatment the results have, in some instances, been more satisfactory than under any other method of using electricity in these affections." The negative pole was placed on the epigastrium and the positive on the back, moving it by turns along the whole length of the spine.

The sand blast is now used for cleaning the fronts of buildings. It is said to accomplish the removal of the dust and soot without injuring the ornamental carvings.

In a paper presented to the Academy of Medicine of Paris, M. Lecorché advances the opinion that diabetes is a secondary disease, attending upon imperfect assimilation of nitrogenized bodies. The large quantity of urea daily voided by the patient, consuming in its production the oxygen which should have been employed in the oxidation of sugar. The latter body consequently finds its way out of the system by the kidneys. The proper treatment, he thinks, is to endeavor to diminish the production of urea by the use of opium, arsenic, valerian, and in some cases bromide of potassium.

As the result of a series of experiments to determine the power of a sphere of iron to retain electricity of various temperatures, F. Guthrie finds that at 84° c. both kinds of electricity are retained; between this and 116° c. negative electricity is discharged and positive electricity retained, while at 140° c. both kinds are discharged equally,

The Italian section of the Vienna Exhibition contained a table-top composed of portions of human muscles, fat, sinews, and glands; all petrified into a single block by Mazini's process, and polished until its surface resembled marble..

Since the English troops were sent to the Gold Coast, the suffering from fevers has been so severe that out of one hundred men only twenty are fit for duty. To avoid this fearful loss, it is proposed to construct at once a railway some thirty or forty miles in length, by which the men may be quickly transported across the pest-stricken margin of the

coast.

The recent death of an English Government clerk, who, according to medical evidence, must have died from syncope, induced by excessive smoking, while the stomach was empty, causes the

Lancet to say: "We have never underrated the danger to which immoderate smokers are liable. Fortunately, the poisons contained in tobacco smoke find a ready exit from the system, but when inhaled during a period of fasting, their injurious effect on the heart is especially to be apprehended."

The Lancet relates the following strange story: "Before Eli H— was born his father made a vow that if his wife should bring him another girl,-she then having had three in succession,-he would never speak to the child as long as he lived. The child turned out to be a boy, and now, what is most strange and remarkable, occurred: this boy would never speak to his father. Moreover, during his father's lifetime he would never speak to any one but his mother and three sisters. As soon as his father died, he then being thirty-five years old, his tongue was unloosed to everyone, and he has remained an ordinarily loquacious individual ever since."

The events of the last year have strengthened the arguments in favor of an Arctic Expedition. Thus the fact that a ship can pass up Smith Sound to 82° 16' N., without check of any description, unknown before, is now established, as well as the constant movement and drift of the ice in the strait, leading to the unknown region. The revolution in ice navigation, caused by the use of powerful steamers, is also more fully understood and appreciated through the report of Captain Markham.(Nature.)

Rubber may be fastened to metal by a solution of shellac in ammonia. One part of pulverized shellac is soaked in ten parts of ammonia; this, in three or four weeks, becomes liquid, and is then fit for application.

When alkaline solutions of copper, nickel, lead, silver, cadmium, tin, and zinc, are heated with a solution of phosphorus in benzine, the metal is precipitated. (A. Oppenheim.)

Wibel states that a species of pond-weed, Potamageton, possesses the powers of precipitating carbonate of lime with which it becomes incrusted.

In a work on the phosphatic deposits of Russia, Alexis Yermoloff remarks: We do not think that we exaggerate when we say that Central Russia reposes on phosphate of lime, with which she is able to pave half of Europe The area of this deposit,

between the Dnieper and Volga rivers alone, is estimated at fifty millions of acres.

W. Müller states that, in a series of experiments recently made, frogs that were frozen in blocks of ice for eight hours were alive and breathed normally as soon as the ice was thawed. Of two of these creatures of equal weight, the most voracious consumed the most oxygen.

Rubber bands may be made from a solution of rubber in a mixture composed of benzine, five parts and fine turpentine, seven parts. The benzine and turpentine must be free from oil and fatty matters.

According to Pettenkofer, cholera patients may be attended with perfect impunity if proper attention is paid to cleanliness. In addition to the ordinary cleansing of rooms and utensils, he especially insists on the immediate subjection of all soiled linen or other clothing to the action of boiling soap-suds.

Metals may be made to adhere to glass by a ce. ment composed of powdered litharge, two parts, dry white lead, one part, boiled linseed oil, three parts, mixed with one part of copal varnish to a thick paste. (R. Franke.)

Where drain pipes in fields have been coated with gas-tar, all difficulty about choking with roots is avoided; for the roots turn away from the tar as though they were sensible of their danger.

The Engineer states that the crude ammonia salts obtained in the manufacture of gas frequently contain sulphocyanides, which destroy the crops to which they are applied.

A coal field, with seams varying from five to thirty-five feet in thickness, and extending over a region of 250,000 miles, has been discovered in the new territories on the line of the Northern Pacific railroad. (Iron.)

The Encalyptus globulus, an Austrian tree, is said to absorb an enormous quantity of water from the soil. It also emits an antiseptic camphor-like odor. These properties have caused it to be employed with success in destroying the emanations in malarious districts.

The vitiated air that escapes from the diver's helmet has been applied by M. Pasteur to support the combustion of a petroleum lamp. This the diver carries in his hand, and so avoids the use of the expensive electric light.

Frankland and Lockyer have found that if we increase the pressure of hydrogen while an electric current is passing through it, the lines gradually expand until the spectrum becomes continuous, and

finally the resistance becomes so great that the electric current ceases to pass.

The Agriculturist states that a very fine white vinegar may be made from the juice of the white part of watermelons. At a certain stage the fluid is bitter, but when perfected acquires a true vinegar flavor.