DREDGING
DRESDEN
the color-spot coming with further development. Drawing for its own sake, or nicety of drawing, is a thing beyond his comprehension until he reaches the higher grades To lead into more refined drawing through his awakening interest in the shapes of the color-spots he has occasion to employ, both in his design and in his representative work, would seem to be a true way of recognizing both his capabilities and his interests
In the older art-schools it has been the practice to teach drawing by setting the student to work in charcoal or crayon from plaster casts of geometric or vegetable forms, or of fragments of the human figure, or even to have him begin by copying plates made from drawings of this kind, this work to lead ultimately to drawing from casts of the whole figure or of groups of figures, and thence to drawing and finally painting from the live model. The reverse order of work is now beginning to obtain, however, and in some modern art-schools students begin their study from the live figure in motion, and as knowledge of detail seems to become more necessary they turn to the cast, leaving the close study of the details of the figure to the last.
The educational content of drawing sums itself up about as follows: Drawing of itself may and probably will lead to an appreciation of beauty of line. It will also develop accuracy of vision. It demands a nice condition of muscular control, and it involves a complete acquaintance with the conventions of projection-perspective.
GEORGE WILLIAM EGGERS.
Dredging, the excavating or scooping out of soil, mud, sand or rock under water by a machine called a dredge. Dredging is used in deepening and widening the beds of rivers, canals, harbors. The forms of modern dredges are very numerous, different conditions requiring different forms, A common form is that in which a large number of buckets or scoops is attached to an endless chain or a wheel. As the chain revolves, the buckets are filled and raised in succession and emptied at the top into a barge for that purpose. Another common form is the single scoop or dipper dredge. of the Osgood or other type. On a long arm, which can be let down and moved along the bed of the stream, is a scoop of suitable form, which can be thus filled, and when filled can be raised and emptied. Other machines include the clam-shell and oyster-dredge, the grapple and the suction-dredge, besides those used in deep-sea dredging. These latter collect samples of sea-bottoms, for the inspection of marine plants and animals. Another purpose of deep-sea dredging is to ascertain the nature of the ocean-floor, so as to determine its suitability for the laying of cables. Soundings for this and other purposes have been made, often at great depths, as in the
explorations of the Albatross, of the U. S.
Fish-Commission, which has made tests of the sea-bottom and brought up deep-sea life at depths varying from 4,000 to 5,000 fathoms. Modern dredges are operated by
A SCOOP-DREDGE
powerful steam-engines, and are strong enough to remove materials of any sort, even 7o-ton boulders. Some dredges have a capacity of over 1,000 cubic yards an hour. Dredging is also done by means of streams of water maintained in pipes by centrifugal pumps. The material to be removed is mixed with the water and carried along the pipes to the point where it is to be deposited in nearly level beds. This method is adopted for sand and soft mud, and has been extensively used in Holland and in San Francisco harbor, where the dredged material is used to fill low ground. Under special conditions pneumatic excavators have been used. In these the materials are drawn into pipes by the suction due to a vacuum. Such an excavator was used in the construction of the great Tay bridge, Scotland.
Dreibund, The, or Triple Alliance, is a league between the European powers of Germany, Austria and Italy, formed for the purpose of mutual protection, in the case of attack upon any of them by other nations. The league was formed in 1882, and has since been renewed. Prior to 1882, however, a league, known as the Dual Alliance, had been in existence since 1879 between Germany and Austria; and in 1882 Italy was admitted to the compact, which is now known as the Dreibund—an important safeguard in the maintenance of the balance of power on the European continent.
Dresden (drez'den), one of the largest cities of the German empire and the capital of Saxony, is situated in the beautiful valley of the Elbe. The city lies on both sides of the river, the old portion on the left bank having narrow, gloomy streets; while the streets of the newer part are wide and regular. Dresden is often called the German Florence, because of its many objects of high historic value. Many of the churches are of historic interest, and the palaces are beautiful buildings, containing fine collections of celebrated works of art. The oourt-
