Page:Popular Science Monthly Volume 5.djvu/134

124 Academy, another letter from Mr. Croft was read, in which he stated that he had found a native of the island who could read them, and who was going to teach him the language, so that he will shortly be able to translate them. Mr. Croft thinks that he has discovered the relics of a great Malayan empire, which extended its power over that part of the ocean at some former period of the island's history.

Deposits in Steam-Boilers.—Prof. S. Dana Hayes, writing in the American Chemist about deposits in boiler-flues, says that they are of two kinds, both of which are capable of corroding the iron rapidly, especially when the boilers are heated and in operation. The most common one consists of soot (nearly pure carbon) saturated with pyroligneous acid, and contains a large proportion of iron if the deposit is an old one, or very little iron if the deposit has been recently formed. The other has a basis of soot and very fine coal-ashes (silicate of alumina) filled with sulphur acids, and containing more or less iron, the quantity depending on the age of the deposit. The pyroligneous deposits are always caused by want of judgment in kindling and managing the fires. The boilers being cold, the fires are generally started with wood; pyroligneous acid then distills over into the tubes, and, collecting with the soot already there, forms the nucleus for the deposit, which soon becomes permanent and more dangerous every time wood is used in the fireplace afterward. The sulphur-acid deposits derive their sulphur from the coal used; but the base, holding the acids, is at first occasioned by cleaning or shaking the grates, soon after adding fresh charges of coal. Fine ashes are thus driven into the flues at the opportune moment for them to become absorbents for the sulphur compounds distilling from the coal, and the corrosion of the iron follows rapidly after the formation of these deposits.

Conditions affecting the Sex of Off-spring.—In the American Naturalist for January, Dr. John Stockton-Hough has an elaborate article on "The Relationship between Development and the Sexual Condition in Plants." His conclusions are: 1. That in plants, and animals as well, that are actively occupied in vegetative, physiological, pathological, or other efforts which are antagonistic or complementary to the office of reproduction, the proportion of females born during such times is greater than where the plant or animal has reached full developmental maturity and growth, is in good health, and is occupied principally in the process of reproduction. In the latter condition offspring of a higher developmental condition are produced, and the proportion of males is increased. 2. Females are in better condition, more troubled by disease, or other process antagonistic to reproduction, where they conceive with females than with males; and they are poorer, because more exhausted and less healthy, by the production of female offspring, than by male products. 3. It is just possible that the ovules from which females are derived may have a higher initial vitality, though they be less highly developed than those from which males are derived, yet no egg can properly be said to be predestined to be male or female. 4. That female plants, like female animals, are less highly developed than males, and are the result of an inferior developmental reproductive effort on the part of the female parents.

Axial Buds in the Juglans Nigra.—In most plants there is a single bud in the axil of the leaf known as the "axillary bud." In the hickories, walnuts, and some others, there are two or more, one above another, known as supra-axillary buds. When remarking on the sexual characters of the buds of Juglans nigra, before the Academy of Natural Sciences of Philadelphia, the specimens I used in illustration made this clear. The abstract in for April states that the several-sized buds are on the same tree. It should be at the same node or axis. Of the three buds, one above another, the upper or largest produces a strong branch; the second in order and in size, a female flower; and the lowest, smallest, and least organized, the male catkin. The illustration is very pretty. No one should be satisfied to read about it, but examine the walnut-trees and see for himself.