Sayfadaki görseller
PDF
ePub

In regard to railroad work the students should be given practice, not only in railroad location and the details of laying out new work, but should also have practice in re-running old lines, re-establishing the grades and centers, and in laying out yard work.

In railroad location the general principles should be explained fully before the field work begins. In selecting a section of country it is advisable to take two towns, ten or twelve miles apart, and have the student make a thorough reconnoissance of the country between them. The methods used should be similar to those used in actual practice, and there should be a time limit in all this work to which the student should be strictly held. Each student should present a written report with sketches of the country and give clearly his.

reasons for considering any one possible line better than another. The preliminary line should be run, and each day's work platted that night. This preliminary line should be run the whole of the distance between the towns and preliminary estimates made. A final location of two or three miles is usually sufficient. After the final location has been made, slope stakes should be put in and final estimates, with plans, profiles, and a written report as to probable cost, etc., made.

Although only land surveying and railroad work have here been considered, the same principles apply to sanitary, hydraulic, or any other branch of engineering.

In regard to field equipment, it is not necessary to go into details as the equipment required depends entirely upon the character of the work done, and any person capable of preparing a course of instruction in Civil Engineering can experience no trouble in making out a list of the instruments necessary for the proper giving of this instruction. There is, however, one instrument for field work that has never been appreciated by American engineers, either as practicing engineers or as instructors, and that is the plane table used with a telescopic alidade containing stadia wires. One reason of this non-appreciation of the plane table is due to the excessive weight and faulty construction of the earlier types, but during the last six years plane tables weighing no more than ordinary transits have been upon the market, and constitute a most valuable instrument for topographical and preliminary work.

In instruction in field work care should be taken that the student gets the correct idea of the relative amount of refinement required in the different operations, so that he may not waste time in calculating earth work to three or four decimal places, but that he may also understand what operations need excessive refinement. In conclusion, it may be said that in our Ameriaan schools of engineering with only a four years' course, the amount of time devoted to field practice, or instruction in practical details, should be limited to the minimum amount necessary for correct instruction in such elementary practice as the student will be called upon to do immediately after graduation, and the remainder of the time should be devoted to the thorough understanding of the general principles and theories that form the foundation of the art of engineering.

DISCUSSION.

PROFESSOR MONROE gave an account of the field practice work in surveying at Columbia College. The work was formerly done in New York City, and through the co-operation of the Central Park Commissioners, was done in Central Park during term time. The park offered a very fine field for the work; a great deal of variation in topography, and an admirable chance for instruction in the various branches of engineering. It was found, however, that there were several objections to doing the work in term time, and doing the work so near a large city, and especially in a finished park, and after six years it was decided to abandon the work there and to try to do it some distance from town in the country. It was found this could be done by using express trains, running to a near point with no greater loss of time than had been incurred in doing the work in Central Park, and with very great advantages, in that the work was not interfered with by others. It was found, however, that this plan did not overcome all the difficulties.

The chief objections that were found in doing work in term time were, first, the loss of the students' time in going to and from the work; it would take from half an hour to three-quarters of an hour to go and come, and of course that was a very large slice taken out of the afternoon. Of course, the conditions are peculiar in New York City, and colleges in the country would not have the same difficulty. There is, however, another objection which applies to doing work in term time, which is common to all schools, and that is the fatigue of outdoor work in the afternoon, especially to students who, perhaps, have been working all the winter over their books, the fatigue and exposure to air and wind and sun in the afternoon produce a heavy, drowsy, sleepy feeling in the evening, and the result was that the work of preparing for the next day's recitations was very severely interfered with by this afternoon work. There were many other reasons which led to the next step, which was to place the surveying in the summer, and to do the work at some distance from New York in a cool, comfortable locality in the Berkshire hills of Connecticut. The work went on there for some seven years in the vicinity of Litchfield, Conn., and on ground that was given for our use by some of the residents. They permitted us to make use of their property for surveying purposes. Fortunately Litchfield is in a dairy country, there were very few crops to be interfered with, the work was done in the last part of the summer when the only crop, the hay crop, had been harvested, so that the work could be done with very little interference.

The advantage of moving to the country was felt at once. The students worked from seven or eight o'clock in the morning until dark, often taking their lunches into the field with them, so as to work continuously, and they would accomplish more in a day than they would in nearly a week under the former conditions, because their work was uninterrupted. In a day you can get eight or ten hours of uninterrupted work, whereas, when afternoons of term time were used, what with the loss of time in going to and from work, setting up instruments and putting them away again, one would hardly have an hour and a half or two hours available time in the afternoon; so that a day in vacation is almost equivalent to a week of afternoons in term time. Of course, Saturdays under the plan of doing the work in term time would count a full day. Another advantage of doing the work in summer was that it was possible to require accurate work on the part of the students, the stakes not being interfered with, the students having plenty of time to do the work, there being no interruptions or loss of time or loss of stakes, it was possible to keep the students up to a very high degree of accuracy.

Finally the next step was taken, the last step, and that was to rent a farm, and now Columbia College rents a farm of about one hundred and twenty-five acres, which was chosen for its topography in order to give as great a variety of surface as possible, and on this farm now all our surveying work is conducted. We have a lease of five years with the privilege of five more, practically ten years, and we shall probably buy the farm at the end of the lease as a result of our experience. In regard to the work itself there are two or three points that as a result of this seventeen years of experience have developed themselves, which are somewhat peculiar, and which characteristics have

« ÖncekiDevam »