THE POPULAR SCIENCE MONTHLY.
them only by referring them to some central organization and direction like the newly established institute.
Action of Citric Acid on Minerals.—Professor H. C. Bolton read a third paper at the recent meeting of the American Association on the decomposition of minerals by citric acid, detailing the results of his later researches on the subject. Some of the conclusions expressed in the first of his two previous papers were modified in the second paper, in view of the results obtained by the prolonged action of the acid. In the third series of experiments Professor Bolton found that many species which resist the brief action of a boiling concentrated solution of citric acid are more or less completely decomposed by prolonged contact with the same solution at the ordinary temperature of the work-room. He has drawn up a table, in accordance with the last series of tests, of thirty-two minerals or classes of minerals which are classified as those that are quickly, slowly, very slowly, or not, decomposed by citric acid.
In an American Association paper Dr. Britton describes a Post-Tertiary, pre-glacial deposit, near Bridgeton, New Jersey, compact enough to furnish a building material, which contains casts of the shells of the hard clam, with silicified wood, and in which very fine impressions of leaves—including those of the sweet-gum, or liquidambar, viburnum, zizania, and elm—are occasionally found.
According to the Census Bureau's bulletin of the statistics of the lumbering industry of the United States for the year ending with May last, $181,186,122 are invested in 25,708 establishments for the preparation of lumber, and the total value of the products for the year was $233,367,729. Michigan leads the States in this industry with 1,649 mills, $39,260,428 capital, and $52,449,928 of products. Pennsylvania is second, with 2,827 mills, $21,418,588 of capital, and $22,457,359 of products. Next are Wisconsin, with $19,824,059 of capital, and $17,952,347 of products; New York, $13,230,934 of capital, and $14,356,910 of products; and Indiana, with $7,048,088 of capital, and $14,260,830 of products. Maine, which used to be considered emphatically the "lumber State," is now seventh in rank, having 848 mills, with $6,339,396 of capital, and $7,933,868 of products.
Dr. Desiré Charles Van Monkhoven, who died on the 25th of September last, just forty-eight years old, was at once distinguished as an astronomer, a chemist, an optician, and a photo-chemist, and was also an active and capable man of business. He was best known by his researches in optical questions bearing on photography, and particularly by his practical applications of them in the Monkhoven solar enlarging apparatus, the Monkhoven tissue for carbon printing, and the Monkhoven gelatine plates, which he invented, and of which he directed the manufacture. He was the author of a general treatise on photography and of papers on his spectral and other researches, contributed to various periodicals.
On the 22d day of April, and on rainy days afterward, the water in some parts of the city of Lille became unfit for use. M. Géard, investigating, found the cause of the trouble to be the growth of a mucidine of the genus Cremotryx, which, greedily absorbing iron, produces in the pipes masses of ochreous matter, the putrefaction of which disengages sulphureted hydrogen in considerable abundance.
A venomous lizard has been presented to the Zoölogical Gardens of London by Sir John Lubbock. It is called Heloderma horridum, or horrid warty-skin; it is from Mexico, and is described as about "one foot and a half in length, of a somewhat thickish form, and with a rather short, pointed tail. Except in color its aspect is not prepossessing." It is of a pale ochre, or corn-color, coarsely reticulated with black marks. All of its teeth are connected with poison-glands.
Mr. W. O. Crosby, of Boston, proposes to account for the origin of the seams running in three directions, by which many rocks are cut up into rectangular blocks, as from earthquake-action. Professor H. F. Walling, of Washington, agrees with him. When the papers of these gentlemen were read in the American Association, Professor Newberry, having expressed a sense of obligation to the authors for bringing the subject forward, said that he was inclined to think magnetic currents may have had some part in the production of the joints. Professor Hall called attention to the joints in the clays at Albany, which could not well have been subjected to pressure.
A correspondent of the London "Daily News" states that some interesting objects have recently been found in Neufchâtel which are considered by Swiss archæologists to throw a new light on the history of the lake-dwellers. Among the objects are a carriage-wheel with an iron rim, iron swords, and many human bones.