Laboratory equipment

“ An equipment of meters, resistance units, Wheatstone bridges, potentiometer sets and traction permeameter is provided for elementary electrical measurements.
Strength of Materials Laboratory
The Strength of Materials Laboratory has been designed for the purpose of student instruction. With this in mind, the size of the apparatus has been kept within moderate limits so that the student may perform the test. The laboratory is housed in two adjoining rooms. The first room is equipped with:
1—100,000 lb Olsen Std. Tension Compression Test Machine. 1—50,000 lb Machine of the same sort. ”

“ During his senior year in the high-school, the chemical and physical apparatus of the laboratory of the school was placed under his charge. In this year he constructed an electric motor having its field magnets as well as its armature excited by the electric current. He also constructed a microscope and a telescope, making all the parts himself, down to the grinding of the lenses. He devised an apparatus for turning on the gas in the street-lamps of Cleveland, lighting it and turning it off again. ”

“ Many laboratories in this country, especially in the west, are located a long way from any professional glass-blower, and the time and money spent in shipping broken apparatus several hundred miles to be mended could often be saved if some of the laboratory force could seal on a new stopcock, replace a broken tube, or make some temporary repairs. Many men in physical or chemical laboratories have occasion to modify some piece of apparatus designed perhaps for other uses, or to design new apparatus. ”

“ Besides the various rooms for researches in chemistry, pur et simple, there are numberless apartments exclusively intended for investigation in optics, electricity, mechanics, and so forth. Motive-power is provided for by a steam-engine of great force, which is connected by means of bands with wheels in the several laboratories. Again, besides the ordinary pipes carrying coal-gas, there will be a series of pipes supplying oxygen from retorts kept constantly at work. Indeed, altogether the new laboratory will be a species of Elysium for the chemical investigator. ”

“ The man test laboratory described above provides facilities for obtaining information concerning the efficiency of canisters, facepieces, etc., within very short periods of time, without waiting for the construction of special apparatus required for machine tests. To get satisfactory results from machine tests, a delicate qualitative chemical test for the gas is essential. Man tests can be made when such a qualitative test is not known. Further, man tests can be made with higher concentrations of some gases than is practicable with machines. ”

“ The microscope required for bacteriological studies should be perfect in all its parts. With regard to the choice of an instrument, it is very much a matter of price, since the most perfect is usually the most costly; I shall therefore proceed to give a typical example of the instrument in use in a bacteriological laboratory. The microscope should possess the following qualifications, all of which are absolutely necessary for the study of such minute objects as bacteria and other micro-organisms. ”

“ The central piece of apparatus of the Institute laboratory is the Emery machine, similar to the great machine at the Watertown arsenal, with a capacity of three hundred thousand pounds. But in addition to this machine there are a dozen or more other machines designed to test beams, columns, rope, wire and, in fact, materials of every kind and in every form. An interesting machine is that for testing shafts in torsion, and it is instructive to see it twist off with apparent ease a steel shaft three inches in diameter, twisting the fibers before they break till the rod resembles a barber's pole. ”

“ The laboratories are large, intended for several students working together, or small, for individual workers. At the present time, students are pursuing investigations upon the mechanical equivalent of heat and the coefficient of viscosity of a liquid. There are eight or ten of these individual laboratories for single students, each supplied with all needed facilities. Every laboratory room, large or small, is supplied with gas for light and fuel, electricity for light and power, water, compressed air, and vacuum pipes. ”

“ Now, my good friend, your living body, and my own, are laboratories, in which changes of precisely the same kind are constantly brought about; your living body, and my own, are made of an enormous quantity of separate chambers and vessels, very small, it is true, but nevertheless such as can be seen quite distinctly when they are looked for with the microscope. In these small chambers and vessels different kinds of substances are thrown together, exactly as the zinc, and acid, and blue vitriol are in the laboratory-chambers of the electric telegraph. ”

“ Shelves, supports for apparatus, and drawers, should be provided in abundance. The fine balances and other delicate instruments should be kept in a separate apartment. With regard to apparatus, we may state that the articles most frequently required in a laboratory are the gas or alcohol lamps; iron pans for sand bath and water bath; evaporating dishes; precipitating jars, funnels, and wash-bottles; retorts, flasks, and test-tubes; mortars and pestles; retort- and filtering-stands; rat-tail and triangular files, and glass rod and tubing. ”

“ There is, indeed, little to see that would greatly interest the casual inspector, for in its outward aspects one laboratory is much like another, a seeming hodgepodge of water-tanks, glass jars of specimens, and tables for microscopes. ”

“ In a large diagnostic laboratory, or in one intended for teaching and investigation, there are numerous accessories necessary to modern microscopic technique. For the observation of living objects a warm stage is needed. The simple electrical apparatus devised by Ross is the most convenient form, as it can be slipped on and off the slide without changing the focus. ”

“ This instrument (in size like the Ib.) combines all the essential features of a large laboratory microscope with a folding stand. It will be found invaluable on scientific expeditions, for research work etc.
When lifted out of the case, spread the two parts forming the base, which are then held by a spring-catch. After raising the tube, turn the stage around and tighten it by means of a lever. It is supplied with large Abbe condenser and Iris diaphragm adjustable by side screw. Coarse adjustment by rack and pinion, fine adjustment by micrometer-screw. Graduated draw-tube. ”

“ For ordinary household use, the apparatus required includes a new, firm tape measure, yardstick, accurate beam scales, and cards for testing vision. For school or institutional work it is desirable to have also calipers, laboratory apparatus for taking heights, instruments for taking blood pressure, and a dynamometer for testing strength of muscles. Economic and social conditions, differences of race and heredity, will cause considerable variation among children of the same age. ”

“ In our laboratories, water and ternary compounds are rapidly decomposed by the battery, and we may reasonably suppose that that which is effected in our laboratories by artificial means takes place in the great laboratory of nature on a grander and more extended scale. ”

“ If a teacher remains sterile both in himself and his students he has missed his vocation.
Of importance equal to that of an efficient body of teachers are adequate laboratory facilities both for teaching and research. Medical science has moved beyond that stage when a student could be kept profitably employed with a microscope and a box of slides. With the growth of laboratory methods of diagnosis, more varied and costly apparatus is needed, more space to place it and more laboratory service to guard it. ”

“ The starting of the National Physical Laboratory for the purpose of testing and standardizing and for research on physical constants promises to be of great value. The simple standardizing of screws and nuts will be a great assistance to manufacturers. ”

“ This principle has been applied to our machinery as well as to our workmen, with the result that we have gradually accumulated a large plant of special machinery of the most accurate construction, each machine especially adapted to the manufacture of some particular part of our microscopes. By this development of mechanical appliances for microscope manufacture two ends have been attained:—The greatest accuracy and uniformity of construction of our microscopes has been made possible, while at the same time it has been possible to cheapen the cost of manufacture. ”

“ Flat-topped tables, not over 30 inches high, a few compound microscopes (one is much better than none) , as many simple lenses, or, far better, simple dissecting-microscopes, as there are students, dissecting-dishes, a pair of bone-clippers, one injecting-syringe, a bunch of bristles, water, a few simple reagents and some inexpensive glassware, as slides, cover-glasses, watch-crystals, and fruit- or battery-jars for live cages and aquaria, make up a sufficient equipment for good work. Much can be done with less, and perhaps a little more with some additional facilities. ”

“ There is a laboratory for general physics, one for electrical measurements, two rooms devoted to a laboratory for electrical engineering, containing two distinct power plants driven by steam engines of 100 and 150 horse-power, with a large number of dynamo machines, transformers and a great variety of other apparatus arranged for purposes of instruction, the mere enumeration of which would occupy several pages. ”

“ It is true that in a well-appointed laboratory, where apparatus is collected together in greater or less profusion, the appeal is often very indirect, and to a student carrying out a set experiment with apparatus provided to his hand, the temptation to ignore the mechanical basis of his work is often irresistible. ”

“ About 300 samples are examined each month, requiring an average of 12 determinations per sample, or about 3,600 determinations per month.
The chemical laboratory for testing Government purchases of structural materials is equipped with the necessary apparatus for making the requisite physical and chemical tests. For the physical tests of cement, there are a tensile test machine, briquette moulds, a pat tank for boiling tests to determine soundness, water tanks for the storage of briquettes, a moist oven, apparatus to determine specific gravity, fineness of grinding, etc. ”

“ Centrifuge tubes, plastic, 15-mL, with screw caps. 11. Scintillation vials, 20-mL, glass, with PTFE-lined screw caps. 12. Assorted beakers (and possibly Erlenmeyer flasks) , various volumes. 13. Volumetric flasks, 25-, 100-, 250-, and 1000-mL. 14. Forceps, PTFE-coated. 15. Glass or plastic rods. 16. Disposable gloves, plastic or latex. 17. Laboratory wipes. 18. Portable power ge nerator (if necessary) . NOTE: If no power supply is available at the field site, electric power can be provided by means of a portable, gasoline (or othe r) genera tor. ”

“ When one first steps into the laboratory, there creeps over one a fear to move, for everything seems a frail meshwork of glass; straight and spiral tubes, glass cylinders, thermometers, barometers, test tubes, bottles, and glass articles, too numerous to mention, are attached to all the available surface on the walls, the shelves and even the ceiling. ”

“ But if you would see the most wonderful things in this laboratory—or rather, to be quite accurate, I should say, if you would stand in the presence of the most wonderful things—you must go with Professor Ramsay to his own private laboratory, and be introduced to some little test-tubes that stand inverted in cups of mercury decorating a shelf at one end. You would never notice these tubes of your own accord were you to browse ever so long about the room. Even when your attention is called to them you still see nothing remarkable. These are ordinary test-tubes inverted over ordinary mercury. ”

“ Before buying a microscope the student should obtain an illustrated price list from any of the firms mentioned above, and, having selected an instrument, he should test it very carefully, or better get some experienced friend to test it for him, before deciding to purchase it. Delicate test objects such as diatoms, scales of butterfly’s wing, or a stained specimen of micro-organisms should be employed. The coarse and fine adjustments should be tried. They should work freely and smoothly and without any delay. ”

“ The laboratory desk, and all apparatus, should be scrupulously neat and clean at all times. A sponge should always be ready at hand, and desk and filter-stands should be kept dry and in good order. Funnels should never be allowed to drip upon the base of the stand. Glassware should always be wiped with a clean, lintless towel just before use. All filters and solutions should be covered to protect them from dust, just as far as is practicable, and every drop of solution or particle of precipitate must be regarded as invaluable for the success of the analysis. ”

“ The portion of the machine destined to carry the tubes should be a metal disc, of sufficient weight to ensure good "flank" movement, continuing over a considerable period of time. In other words, the machine should run down very gradually and slowly after the motive power is removed, thus obviating any disturbance of the relative positions of particulate matter in the solution that is being centrifugalised. ”