PHYSICAL LABORATORIES. specially equipped for physical experimentation were not provided until long after well-organized chemical laboratories were in use. Such early experi menters as Boyle. Newton. and Franklin made use of their own living apartments for their ex periments, and it was not until well into the nineteenth century that professors of physics obtained separate rooms in which they could carry on work with due convenience. The next step was for these professors to admit students to their own laboratories, and to dime( their re search. At Heidelberg, the first physical labo ratory- was opened in 1846. two rooms being de voted to instruction in practical physics. The laboratory at the University of nlasgow where original 'research was carried on by students under the direction of Lord Kelvin was also one of the earliest of these laboratories. In France, in spite of the brilliant work done in private laboratories in the first half of the nineteenth century, the facilities for systematic work by students were hardly as ample as in normally, but by ISGS it was realized that additional ae commodations for students and research labo ratories for professors and skilled investigators were essential. One result of this movement was the foundation. in the Sorbonne in Paris, of a physical laboratory. of which Jamin was made director, and which has been celebrated not only for his researches. but also for those of Lippman. This laboratory was placed under the direction of the faculty of science in ]SO4 and was then remodeled. King's College. London. also adopted regular laboratory training as part. of its work in physics about this time, and three rooms in its building were used as a laboratory. The first building in England specially designed for the study of experimental physics was con structed at Oxford, under plans of Prof. Robert B. Clifton. This was followed by the Cavendish laboratory at Cambridge, built in 1874 by Prof. James Clerk-Maxwell, who incorporated in it many of Professor t Iiiton's ideas. In the United States the progress was naturally slower than in Europe, nut it is asserted that the first insti tution to make laboratory physics a part of its regular educational work was the Massachusetts Institute of Technology, in Boston. The sys tematic work begun at the Massachusetts In stitute of Technology in practical physics fur nished an example which was soon followed by other American colleges, including Cornell and Ilarvard, and even by many high schools, and 51, rapid was the progress made that in 1886 Harvard required experimental work in physics in its entranee examinations.
In elementary laboratory work in physies, the apparatus is simple and the results demanded are qualitative rather than quantitative. A laboratory for this purpose would be merely one or more rooms provided with suitable tables. The simple apparatus used should. where possible. be constructed by the student himself, the use of tools for the making, adjusting, and repair of apparatus forming not the least Valuable part of the training. The ordinary manipulation of glass tubes, and the use of the more common wood-working tools, as well as of a few imple ments for cutting and shaping metal, must he learned by the student at an early stage.
The entrance requirements for the colleges have set the standard for the physical work to he done in preparatory schools. No elaborate instruments are required for such courses, and it is considered better practice to have the student work as accurately as possible with somewhat crude apparatus. In the college laboratory the equipment is of a. much higher grade. and should be as extensive as the means of the institution will permit. The student here begins to work quanti tatively, and accuracy of observation and meas urement is the prime essential of his work. The usual method of instruction is to have an ele mentary course which covers the essential fea tures of physics. That is, a student will begin with the ordinary measurements of length. mass, and time. He will perform quantitative experi in sound. beat. light. and eleetrieity. There must he at his disposal measures of length and micrometers of various forms which will enable him to determine length or thickness to one-hundredth of a millimeter. or even less. He will also have analytical balances for determin ing the mass of substances with an accuracy of the one-hundredth of a milligram. and suell other instruments as accurately calibrated thermome ters. standards of electrical resistance carefully determined, and optical apparatus in which the graduated circles and other parts used for meas urement are of high precision. As the construc tion of this apparatus involves considerable me ehanieal skill, it is, of course. impossible for the student to make it but its test and calibration is one of his first tasks. He is taught the neces sity of correcting his ohservations and looking for and compensating for such causes of error as can he detected. and, in short, to attain as great accuracy as the apparatus he uses is capable of.