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district, with a diversified topography well suited for both the transit stadia and the plane table method. The Wisconsin River, the largest river in the state, is close at hand inviting discharge measurements. In June at its usual stage it has a flow of from eight thousand to fifteen thousand second feet. At the present writing this discharge is over forty thousand second feet. The valley of the river is from five to twelve miles wide, with high hills well suited for triangulation work.

Here, also, are located many bench marks whose elevations have been accurately determined by the U. S. Lake Survey, the U. S. Geological Survey, and the State Levee Commission. Triangulation stations of the U. S. Coast and Geodetic Survey are near enough for connection.

As the details of such field work must be very similar on all student surveys it is not necessary to give them here.

The Wisconsin course comprises the following lines of work:

(a) Geodetic.-1. Measurements of a base line over a mile long with a three hundred foot steel tape.*

2. Angles of several quadrilaterals are observed and adjusted (using both direction and repeating theodolites).

3. Latitude, longitude and azimuth are astronomically determined by both approximate and refined field methods.

4. The L. M. and Z. of each station in the net is computed from the adjusted data.

* For a description of methods and results see Vol. XLVIII., p. 132, Transactions Am. Soc. C. E.

5. Long lines of precise levels are run, using instruments both of the Kern and of the new U. S. Coast and Geodetic Survey pattern.

(6) Topographic.-1. A topographic map of the city of Portage is prepared with five-foot contour, horizontal scale one inch equals sixty meters.

2. A topographic map of about fifteen square miles of the surrounding country is made by the stadia and transit or the plane table methods.

3. Each party of two students runs about twenty miles of duplicated wye levels checking on precise level bench marks.

4. One long line of levels is run by each student with an engineer's transit in order to inspire confidence in this instrument as a leveling instrument.

(c) Hydrographic.-1. Three different types of current meters are calibrated and the necessary velocity tables computed for use in discharge measurements.

2. The discharge of the Wisconsin River is measured twice daily, besides which each party makes determinations of vertical velocity curves to determine the relation between the mid-depth and average velocity of section.

3. A hydrographic survey and map of four or five miles of the river or of some nearby lakes is made.

The fact that the work has been duplicated each year has made it much easier to plan and supervise the work. It also allows of a systematic training in a great variety of work. At the same time it is not lacking in novelty to the student.

At first it was difficult to find rooming and boarding accommodations in the better grade of private homes and hotels were used instead. Since the first year, this difficulty has entirely disappeared owing to the reputation which the boys have earned. At the present time applications to room and board the students have been received for double the number required. This is mentioned here because it has been charged that such students could not be depended upon at such time for serious work. It is self evident that the homes of the first citizens could not be open to guests who kept late hours, or who indulged in “hilarity.” No complaint of this character has ever come to the writer.

In order to bring the students nearer their work it is likely that a complete camping outfit will be provided for the survey in the near future.

An offer to publish the maps of the survey has been received from the director of the Wisconsin State Geological Survey. It is a question in the writer's mind, however, whether the interests of the student would not sometimes need to be sacrificed to the needs of the published maps, in case of such an arrangement.

Conditions for Substituting Practical Work. The question of whether such summer school work should be required of all students was quite thoroughly discussed at the St. Louis meeting of this Society and answered in the affirmative.

The practice at Wisconsin is to allow the substitution of professional work for one half of the summer school work. Such work, however, must be instrumental work and the application for credit must be accompanied by letters from the employer, stating the character and amount of the work and proficiency displayed by the student.

The number of undergraduates who can obtain professional engagements in vacation time varies greatly from year to year. Moreover, the value of such work to the student varies greatly. The interests of the employer are apt to keep the beginner at the same thing instead of providing him a variety of tasks. Especially is this true of the first two vacations.

At the present time no argument is required to show the need of a summer school of surveying, where systematic instruction in field work may be given in a large number of lines. The best argument is the uniform testimony of the students who have taken such a course, that their time and money were well spent.

It should be noted that such summer work virtually adds to the length of the course of study; in the case of Wisconsin by one entire month. Nor does this lengthening of the course of study concern the civil engineering students alone. By a recent action of the board of regents, and upon the recommendation of the engineering faculty, the students of the four other engineering courses are required to spend four weeks in the shop work during one of the summer vacations. It is, however, understood that professional employment during one or more vacations in similar lines of work will be accepted as an equivalent of this required work.

This summer school requirement will undoubtedly result in not only reducing the number of subjects during regular term time, thereby permitting of more thorough work, but also, because of the longer and more continuous hours allowed for the work in the summer will largely improve the amount and quality of the shop work itself.

THE CORNELL SUMMER SCHOOL OF SURVEYING.

BY CHARLES L. CRANDALL, Professor of Railroad Engineering and Geodesy, Cornell University.

The work was planned by Professor Fuertes and begun in the spring of 1874 on Cayuga Lake, a lake some forty miles long heading at Ithaca. The object was to give instruction under conditions simulating those of actual work as closely as possible. He had had a large experience in organizing and conducting extensive surveys. The work laid out included the survey of a belt about two and a half miles wide on each side of the lake with transit and chain, together with soundings, based on a triangulation. Both the senior and junior classes were taken to the field. They were organized by the election of a chief engineer and commissary and divided into parties of four to five each, with captains appointed by the instructing force. They were kept in the field two weeks and returned in time to review and take their term examinations. The survey was a success but the reviewing for and passing examinations after a two weeks' bake in the sun was not. The next year the class-room work was completed before the field work began. The work was differentiated, the juniors taking the topographic and the seniors the hydrographic and geodetic.

These surveys were continued on the finger lakes of central New York until 1898, completing all those conveniently accessible from the university. Headquar

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