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288  may be killed. The small flowering species seem to be preferred by the beetles, and are therefore recommended, as the goat's-beard (Spiræa aruncus), sorb-leaved (S. sorbifolia), and meadow spiræa (S.ulmaria). They are, moreover, desirable plants for their beauty.

 

to the beginning of the eighteenth century opium was imported into China in comparatively small quantities, and mainly used as a remedy in dysentery. The vice of opium-smoking began in the latter half of the seventeenth century, but the drug was then too dear to permit the habit to spread rapidly; at the end of a hundred years, however, it had extended over the whole empire. The first edict against the practice was issued in 1796, and since then there have been innumerable prohibitory enactments, but all powerless to arrest the evil, which is now greater than ever before, and increasing in an alarming ratio.

has been convinced, by his studies of the influence of forests upon the moist currents that pass over them, that pines and other needle-leaved trees have a strong attraction for the vapor of water. He believes that the resinous trees transpire twice as much as other trees; and has also observed that when they are exposed to moist air they absorb vastly more water than the latter.

deaths have been recently announced of two of the most prominent entomologists of Continental Europe. Ernest August Helmuth von Kiesenwetter was a member of the Saxon Privy Council, an accomplished and conscientious worker in the science, a considerable traveler, and a close observer. He was chiefly a coleopterist, but attended more or less to all orders of insects, while limiting his studies chiefly to those of Europe. S. C. Snellen van Vallenhoven, of Holland, was best known by his works on the insects of Holland, and his "Entomological Fauna of the East Indies." He also produced a work, which is still incomplete, on the "Ichneumonidæ of North-western Europe." All of his works were illustrated by beautiful and faithful drawings from his own pencil.

is building for an establishment at Noisiel, France, a machine for transmitting electrical force to a distance, with which he expects to gain a normal power equivalent to that of ten horses, and under special conditions a power of sixteen horses.

death is announced of Dr. Wilibald Artus, Professor of Philosophy at Jena, on February 7th last, aged seventy years. Also of Dr. Franz Xaver von Hlubek, Professor of Agriculture at the Graz Joanneum, on February 10th, aged seventy-eight years. In the third week of February also died Herr Adolf Müller, one of the directors of the well-known Geographical Institute of Justus Perthes at Gotha.

investigation into the cause of the fire which broke out on the steamship Mosel revealed the fact that it originated spontaneously in silk goods which constituted a part of her cargo. Chemical examination showed that for every part of silk fiber "0·75 part of oxide of iron and 2∙50 parts of coloring matter—consisting of fatty oils, organic and earthy matters—had been used to give weight and body to the silk."

data obtained by a series of elaborate experimental researches, Professor F. Rosetti estimates the effective temperature of the sun at 9,965° centigrade, taking into consideration the absorption produced by the terrestrial atmosphere. But, estimating also the absorption of the solar atmosphere, and calculating the thermal effect of the sun if it had no atmosphere, the solar temperature would be 20,380∙7° centigrade.

of the British army, and a learned botanist eminent for his thorough and comprehensive knowledge of the grasses, died at his residence near Taunton, England, on the 29th of January, aged sixty-four years.

French Government has taken action with a view to the protection of the domestic birds of the country, prohibiting in the several departments the pursuit of other than birds of passage, and those only under certain limitations.

official reports show that the adulteration of food and drugs has largely decreased in Great Britain under the operation of the legislation against it. In 1856, when the "Lancet" commission made a report of its inquiries on the subject, more than half the samples analyzed were found to be adulterated. The first analysis under the act of 1875 was made in 1877, when it was shown that of the samples subjected to analysis the proportion of adulterated ones had fallen to 19·2 per cent. In 1878 the proportion fell to 17·2 per cent. If spirits be excluded from the calculation, the percentage of adulteration would be represented by 15·5 in 1877, from which it fell to 13·7 in 1878.

French papers chronicle the death, at the age of eighty-two, of Dr. Boisdoval, a distinguished horticulturist, and author of a valuable work on the insects which affect garden-plants. 