Looking closely at the metric system, we must confess its simplicity and symmetry. Like every creation of science, it is according to rule. Master the rule and you master the system. On this account it may be acquired by the young with comparative facility, and, when once acquired, it may be used with despatch. Thus it becomes labor-saving and time-saving. Among its merits I cannot hesitate to mention the nomenclature. A superficial criticism has objected to the Greek and Latin prefixes; but this forgets that a system intended for universal adoption must discard all local or national terms. The prefixes employed are equally intelligible in all countries. They are no more French than English or German. They are common, or cosmopolitan, and in all countries they are equally suggestive in disclosing the denomination of the measure. They combine the peculiar advantages of a universal name and a definition. The name instantly suggests the measure with exquisite precision. If these words seem scholastic or pedantic, you must bear this for the sake of their universality and defining power.
Unquestionably it is difficult for one generation to substitute a new system for that learned in childhood. Even in France the metric system was tardily adopted. Napoleon himself, on one occasion, said impatiently to an engineer who answered his inquiry in metres, “What are metres? Tell me in toises.” It was only in 1840 that the system was definitely required in the transaction of business. Since then it has been the legal system of France. Cloth is sold by the metre; roads are measured by the kilometre; meat is sold by the kilogram, or, as it is familiarly abridged, by so many kilos.
It is generally admitted that the names are too long, although nobody has been able to suggest substitutes, unless we regard the various abridgments in that light. But no abridgment should be allowed to sacrifice the cosmopolitan character which belongs to the system. Thus, in England a nomenclature is proposed which would secure short names; but these would be different in each language, and entirely different from the French names. This is a mistake. The names in all languages should be identical, or so nearly alike as to be recognized at once. This may be accomplished by an abbreviated nomenclature.
For instance, we may say met, ar, lit, and gram; and, in describing the denomination, we may say, in the ascending scale, dec, hec, kil, and in the descending scale, dec, cen, and mil,—indicating respectively 10, 100, 1000, and ⅒, ¹⁄₁₀₀ and ¹⁄₁₀₀₀. Compounding these, we should have, for example, kilmet, killit, kilgram, and cenmet, cenlit, cengram. These abbreviations might be substantially the same in all languages. They would preserve the characteristics of the unabridged terms, so that the simple mention of the measure, even in this abridged form, would disclose the proportion it bears to its fellow-measures. Previous measures have been represented by monosyllables, as grain, dram, gross, ounce, pound, stone, ton. Where a word is often repeated, in the hurry of business, it is instinctively abridged. We shall not err, if we profit by this experience, and seek to reduce the new nomenclature to its smallest proportions.
Twelve words only are required by this system. Learning these, you learn all. There are five designating the different units of length, surface, solid capacity, liquid capacity, and weight. Then there are the seven prefixes, being four in the ascending scale, expressing multiples, or augmentations, of the metre or other units, derived from the Greek, and three in the descending scale, expressing subdivisions, or diminutions, of the metre and other units, derived from the Latin. These twelve words contain the whole system.
In closing this chapter on the unquestionable advantages of the metric system, I must not forget that it is already the received system in the majority of countries. At the Statistical Congress assembled at Berlin in 1863, it appeared that it was adopted partly or entirely in Austria, Baden, Bavaria, Belgium, France, Hamburg, Hanover, Hesse, Mecklenburg, the Netherlands, Parma, Portugal, Sardinia, Saxony, Spain, Switzerland, Tuscany, the Two Sicilies, and Würtemberg. Since then, Great Britain, by an Act of Parliament, has added her name to this list. The first step is taken there by making the metric system permissive, as is proposed in the bills before Congress. The example of Great Britain is of especial importance to us, since the commercial relations between the two countries render it essential that these should have a common system of weights and measures. On this point we cannot afford to differ from each other.
The adoption of the metric system by the United States will go far to complete the circle by which this great improvement will be assured to mankind. Here is a new agent of civilization, to be felt in all the concerns of life, at home and abroad. It will be hardly less important than the Arabic numerals, by which the operations of arithmetic are rendered common to all nations. It will help undo the primeval confusion of which the Tower of Babel was the representative.
As the first practical step to this great end, I ask the Senate to sanction the bills which have already passed the other House, and which I have reported from the special committee on the metric system. By these enactments the metric system will be presented to the American people, and will become an approved instrument of commerce. It will not be forced into use, but will be left for the present to its own intrinsic merits. Meanwhile it must be taught in schools. Our arithmetics must explain it. They who have already passed a certain period of life may not adopt it; but the rising generation will embrace it, and ever afterwards number it among the choicest possessions of an advanced civilization.