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198 to give him the spirit of the method, he will usually comprehend the full significance of others which are plainly exhibited before him.

In the third place, quantitative as well as qualitative experiments are introduced from the first, and all the usual measurements of chemistry are illustrated. Examples are given of the determination of melting and boiling points, the student first constructing the thermometer with which the determinations are made. He further learns how to measure with the calorimeter the amount of heat evolved in chemical processes, and to find the specific heat of the materials used. There are also simple examples of quantitative analysis and of the determination of molecular and atomic weights; and, lastly, easy methods of determining gas and vapor densities place even those measurements within the reach of elementary students.

In the fourth place, great pains have been taken to reduce the expense of the course to the lowest possible point. To this end common household utensils such as may be made by a tinsmith, or found at any house-furnishing store, have been adapted to the purposes of instruction. The small (so-called "American") petroleum cooking-stove serves an admirable purpose for heating, its oven is an excellent drying-chamber or hot-air bath, and, with a simple attachment furnished by the makers, it may be used as a tube-furnace. So also a farina-kettle makes a good steam-bath; and the quick-sealing fruit or milk jars are not only good gas-holders, but enable any student to perform experiments which formerly were only made with costly apparatus. The only apparatus of precision required are the scales and thermometers, which can be purchased from the dealers in chemical supplies at a very moderate cost. Indeed, the expense of the absolutely necessary outfit for a class of twenty students need not exceed one hundred dollars, and twice this sum will purchase everything that could possibly be needed for the course here laid out.

Lastly, the course has been made inductive throughout. It is a wise economy in education to seek from each study that discipline which it best affords. The memory is a greatly abused faculty. The necessities of language, the commonplaces of history, and the requirements of literature and art, task even the most retentive memory, and it is a waste of resources to overburden it with a mass of scientific details which, even if retained, will be of little value except to the specialist. Chemistry is peculiarly an inductive science, and to teach it deductively is to use it for a discipline, which is much better furnished by mathematics or mechanics; yet chemistry is taught deductively whenever, as in most elementary text-books, the chief stress is laid upon the symbolical expression of chemical facts and principles. To secure the peculiar discipline of chemistry, it is essential that it should be studied as it has been built up. The student must begin by observing phenomena, and be led up to the general principles through his own inferences. To begin with an abstract statement of