Page:Popular Science Monthly Volume 7.djvu/261

Rh the origin of every one of the samples. The corpuscles of the human blood averaged $1/3430$ inch diameter, those of the oxblood $1/4874$, and the sheep's blood $1/5952$.

The Cincinnati Zoological Garden.—We are indebted to Mr. G. H. Knight, of Cincinnati, for an account of the Zoölogical and Botanical Garden about to be established in the northern suburbs of that city. The projected garden is to be, as far as possible, a complete representation of the fauna and flora of this continent. Efforts will be made to render the ground a complete arboretum, in which each tree and shrub will be plainly labeled according to the scientific classification, with the common name appended. Fresh and salt-water aquariums, on a large scale, will add to the popular attractions as well as to the scientific value of the establishment. Nor will the collection be restricted to a representation of the animal and vegetable worlds; there is also to be a novel geological feature added, viz., an artificial section of the earth's crust, made up of the actual component rocks in their natural positions, accompanied, possibly, by some of their paleontological characteristics; that is to say, their extinct fauna and flora restored. The tract of land secured for this garden is, for the most part, an elevated plateau of about sixty-seven acres, very central and accessible in location. The Cincinnati Zoölogical Society, to whom all the credit of this great enterprise is due, have already in hand over $100,000 for the beautification of the grounds and the construction of the necessary buildings, laying out of paths, etc. A naturalist, who brings a large practical experience in the care of wild animals, and a landscape-gardener, who has been engaged in similar works elsewhere, have been engaged, and are already busily at work examining the ground and making necessary preparations.

The Dietetic Value of Gelatine.—The theory that gelatine passes through the system undigested, and thus contributes nothing toward the nourishment of its tissues, has recently been subjected to a reexamination by Etzinger, with results that appear to contradict the current view. By submitting fine gelatine, and also the various gelatine-yielding tissues, such as bones, cartilages, tendons, connective tissue, etc., to the action of artificial gastric juice, he shows, in accordance with Boerhaave and others, that gelatine is digestible, breaking up and becoming dissolved more or less rapidly, according to the form in which it is presented to the solvent. Being satisfied on this point, the next question was, "Is the gelatine, after solution or digestion, of any service in nutrition?" To determine this, a careful dieting of animals was instituted, with coincident analysis of their urine and fæces. The results showed that, in the cases of bone, cartilage, and tendons alike, these substances not only undergo digestion, but are absorbed into the blood, and play an important part in nutrition. Instead, therefore, of being entirely cast aside as useless articles, they may be consumed in moderate quantities with decided advantage.

The Origin and Structure of Fulgnrites.—Mr. Frank Buckland publishes, in Land and Water, an account written by his father, the late Prof. Buckland, of certain vitreous tubes discovered in sand-hills, near Drigg, in Cumberland. Three of these tubes were found on a single hillock about thirty feet above the level of the sea, the diameter of each being about an inch and a half. An excavation having been made about one of them, it was found to descend perpendicularly through the sand about thirty feet. At about twenty-nine feet, the sand was succeeded by a bed of pebbles. Here the tube came in contact with a piece of hornstone porphyry, from which it glanced off at an angle and then resumed its vertical position. Below this point the tube, becoming extremely delicate, was frequently broken, and at the distance of a foot the sand fell in, preventing further investigation. The tube appears to have tapered in its descent, its diameter at the bottom of the excavation being only half an inch. Small lateral branches proceeded from different parts of the stem, not over two or three inches in length, nor one-quarter inch in diameter at the points of insertion. They were conical, the points being turned downward. The outside of the tube is coated with an agglutinated sand, which, viewed with a lens, is seen to consist of black and opaque