Page:The New International Encyclopædia 1st ed. v. 05.djvu/782

* CURBENT-METER. 674 CtTRRICULUM. rent, with the bhideil wheel pointing against the cuiTent. The current, striking the blades of the wheel, causes the wheel to rotate at a speed varying with the velocitj^ of the current, and a record of the speed of rotation is kept by means of an electrical circuit which is completed and broken by the wheel one cr more times each revolution. The recording apparatus is kept on shore or in a boat, while the meter is sus- pended by suitable appliances at any point of the stream at which it is desired to measure the velocity of the current. With one exception, which is noticed further on, the chief difference between the different patterns of current-meter now in use exists in the rotating wheel. In the earliest form of meter, invented b.y Gen. Theo- dore G. Ellis, the wheel has helicoidal blades, but in later forms conical cup-shaped vanes are emplo.yed. The invention of the electrical re- cording attachment as applied to current-meters is credited to D. Ferrand Henry, of Detroit, Jlich. The Price current-meter shown in the PRICE CURBENT-METER. illustration has an electrical recording device, and the wheels shown at A are of such shape that they feel the influence of a very slight cur- rent. The weight which serves to keep the appa- ratus submerged is shown at B. The most recent pattern of current-meter is the so- called direction current-meter invented by E. 8. Ritchie and E. E. Haskell, the latter of the United States Coast and Geodetic Survey. With this meter the observer is able to determine simultaneously on recording dials the direction and velocity of any current. This meter consists of a fish-like body, or chamber, mounted on horizontal bearings carried by a ring which encircles the body. To the top of this ring is attached an eye for the suspension-cable con- nection, and to the bottom is attached a similar eye from which the anchor weight is himg. The rear end of the body is prolonged in the shape of a tail-vane, cruciform in section, and the for- ward end terminates in a hollow shaft on to the end of which the wheel-hub is journaled. The wheel is of the screw-propeller type and conical m form, and its rotation is recorded by indica- tors operated by an electrical circuit. The body of the meter is a compass, whose needle is free to assume the magnetic meridian, and by means of an electric circuit the angle between the direc- tion in which the compass-needle points and the direction in which the axis of the instrument points is recorded on a dial. This meter is suf- hciently delicate to record a variation in velocity of current as small as 0.2 foot per second. CURRENT RIVER. A stream less than 250 miles in length, rising among the foothills on the eastern slope of the Ozark Jlountains, in Texas County, southern Missouri. It flows southeast, then south, crossing into Arkansas, where it joins the Black River in Randolph County (Map: Arkansas, El).

CURRENTS. See Ocean Currents; Tides.

CURRICULUM (Lat. curriculum, a running, a course, from currere, to run). The term applied to a course of study, or collectively to that of any type of educational institutions, as the col- lege curriculum, the high-school eurricuhnn, the common-school curriculum, etc. The historical basis of the modern educational curriculum is found in the Seven Liberal Aits of the iliddle Ages, the development of which from Greek phil- osophical speculation and educational jiractices is traced vmder the title of Arts, Seven Liberal. As long as the idea of the symbolical perfection of this organization of studies and of human knowledge prevailed, there was no modification of the form of the curriculum, though the con- tent of these terms was modified from time to time. All lower education was included in the subject of the trivlum — i.e. grannnar, rhetoric, and dialectic — which represented so many ap- )>roaches to the Latin language. This was based, it is true, on the work of the 'singing' school, which furnished to the child the school arts (reading and writing), with a modicum of arith- metic. The curriculum of higher education included the subjects of the qiuidyiriiim — i.e. arithmetic, geometry (mathematics and geog- raphy), astronomy (natural sciences), and music (ipsthetic, etc). The elaboration of the curricu- lum under the influences of the early universities and of the Renaissance consisted chiefly in the addition of the subjects of medicine and law, both common and civil, and in the change in the content of the subjects of the quadrivium. These changes can be followed in the successive Papal rules and university regulations which pre- scribed the books that should be read in the sev- eral subjects. From the time of the Renaissance to the close of the eighteenth century, there Ava.? no modification in the organization of the edu- cational curriculum and little in the content. From that time, however, the changes have been numerous and radical, and the old idea of the historical and logical perfection of the tradi- tional curriculum has largely disappeared. In the United States, where conditions permitted these changes with less opposition than in the more conservative societies, very extensive changes h.ave occurred, and an almost chaotic condition has ensued. These changes have consisted prima- rily in the addition of new subjects to each of the stages of the curriculum, due to the great development of knowledge, especially scientific, during the nineteenth century. The curriculum of the elementary school has expanded in content