opinion
Measure for Measure
O n a recent day in August the New York Times carried two articles; one described an amazing outcome of one of the most outstanding feats in science and engineering, the other was a medieval horror tale. The first story was entitled "Moon Dust Samples Yield Signs of Organic Matter"; the second one, prominently displayed in the front section of the paper, had the astounding title "Inch of Rain Much? On Acre, It Is Put at 27,154 Gallons." (The World Almanac of 1968, p. 60, discussing the same overwhelming problem, comes up with 27,143 gallons!). It turned out that the moon material contained 126 and 30 parts per million of hydrocarbon in the analyzed samples. Of course this refers to either milligram per kilogram or micrograms per gram of matter analyzed. At the same time as the tremendous progress of science is reported, the old-fashioned units, which stem from royal fiat and popular custom and which have been carried along for hundreds or thousands of years, are used to express the measures of rainfall. The explanation of the calculation covers 62 cm2. The calculations required to indicate the amount of water represented by one inch of rain per acre are shown in Table 1. Of course, using the metric system one finds easily that one centimeter of rain falling on one square kilometer of ground represents 10,000 metric'tons of water. I n the first instance it is necessary to consult conversion tables, because it is impossible to remember the bizarre and odd figures which are necessary in non-metric conversions. For the metric conversion it is not necessary to refer to any table at all, and anybody can carry the figures in his head. One could hardly imagine a newspaper article discussing this calculation in metric units, much less one occupyingpart of three columns. However, why should I blame the Nezu York Times for this usage since most other newspapers and magazines do the same? The Geographic Society goes to great length to prepare marvelous maps, undoubtedly a t considerable expense. A sole concession to international readers and to scientific usage is made in the scale a t the edge of maps, which is shown both in kilometers and in miles, while the main portion of the map uses miles for distances, feet for elevations, and fathoms for depth. Text and illustrations in the Geographic Magazine are expressed in "U. S. Customary Units," e.g., feet-pounds-miles-yards-fathoms-ounces, etc. The same is true for a journal addressed to scientists and scientifically-minded readers, such as the Scientific American. I n this journal one can find sketches and maps drawn on a metric grid, while the caption is expressed in feet or miles. I n the journals of the American Chemical Sociely the following policy prevails: I n "scientific journals" only 450
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Journol o f Chemiml Education
Table 1.
I.
Weight and Volume of W a t e r Per Unit Area
U.5. Custmnary Units
Problem: What is the weight and volume of water, which covers 1 acre to a height of 1 in.? A. Conversion of factors 1 acre = 43 560 fta 1 ftP = 144 in¶ 1 gallon (U. S . ) = 0.1337 fta = 231 inJ 1 fts = 1,728 ina 1 ton (short) = 2,000 1h Density of water = 8.345 lb/gal (US.) B. Cdenlations Area: 1 acre = 43,560 X 144 = 6,272,640 = 6,272,640 s Volume: 6,272,640 X 1 231 = 27,145 gal Weight: 27,143 X 8.345 = 2 8 , 6 1 2 Zb = 226,512 + 2000 = 113.23 short tons 11. Met* Unils Problem: What iis the weight and volume of water, which covers 1 kmz to the height of 1 em7 Ares: 1 k m b 1000 X 1000 = 10' mZ = 100,000 X 100,000 = 10" cmP Volume: 1 ma = 100 X 100 X 100 = loBcmS 1010 X 1 = 1010 om3 = 10,003 ma Density of water: 1 g/cm8 = 1 t/m8 Weieht: 10'0 + lo6 = 10.000 t
the metric system is used, while the usage is optional in the "applied journals," and the choice of units is left to the criterion of the authors. I n news reports, generally those units are used which are provided by the source; practically all reports dealing with American chemical industry are expressed in customary units, while many of the items discussing foreign chemical industry and other events of interest to chemists are expressed in metric units. Yet, quite often, one finds these items "translated" into customary equivalents. I n no case are conversion factors quoted. This leads to considerable confusion and a regrettable multiplicity of units. It is easy for those interested in this matter to find examples of this. A good case in point is the Chemical and Engineering News of April 7, 1969. On pp. 12 and 13 strategic requirements of the United States are quoted, expressed as: pounds, short tons, short dry tons, ounces, long tons (reading from top to bottom). This is followed on p. 14 by a table, in which production goals of a French industry are expressed as 10,000 metric tons of heptene, or 30,000 metric tons of cumene. I n the same table, yields are expressed as pounds of product per pound of starting material, water requirements in gallons/ minute; steam as pounds/hour; electricity as kilowatt/ hour. Expenses and investments are given dollars (which are decimal units). On p. 26 butadiene production in Europe is discussed in metric units. I n none
of these tables or articles is any conversion given; yet the articles are presumably directed to the same reader group. 'Confusion now has made his masterpiece!" Macbeth, 11, iii, 71). Tt, -i s- exneeted that the United States will finally come -. around to use the metric system in place of the oldfashioned traditional units. After a prolonged struggle the "Metric System Study Rill" has finally been passed by Congress and the feasibility and ways of converting to the metric system are being investigated. The principal official body engaged in this study is the National Bureau of Standards of the U. S. Department of Commerce. Other private organizations also are studying these matters. I n scientific and engineering reporting it would not be necessary to eliminate all conventional units abruptly. What should be done, however, is to quote all figures both in metric as well as i n customary units.' This can be done easily. A very fine article dealing with chemistry, mainly chemical engineering, in the "Encyclopedia Americana," by W. T. Read, (Annual Supplement, 1967 and 1968) does just what I am proposing. The already lucid article is made even clearer and more palatable to the readers by expressing all values both ways. The "Encyclopedia Americana" also goes further in citing mineral resources of all countries and the amount of ore mined only in kilograms or in metric tons, quoted directly from the source, the U. S. Bureau of Mines. If the engineers and chemists concerned would not care for this method, it certainly would not be used. However, it seems to be readily accepted and must be clear to everybody. The use of the metric system is increasing steadily not only among scientists, hut also among engineers; the use of a uniform system of measure throughout facilitates the transition from bench-work in the laboratory to pilot plant study and to large-scale production. Table 2 lists the results of some recently published polls, which were circulated mainly among engineers. One of the best ways of promoting the increasing use of the metric system among the public is through ~~~
.
~~
~
This procedure is recommended by the U. S. Bureau of Standards for its "technoloeical" iournsls and n a m e [Tech. News Bull., 52, June (196811. 1
Table 2. Tabulation of Surveys For
Source
An- Metric swers System
"Industrial n Jan. 1967, "Oceitna nati Jan./I . ... "Design News" March 31 1965 (Total) 1204 "strong &inion" 877
965 702
%
Against Metric System 470
70 58
"Partially" and "No opinion" omitted.
the schools; unfortunately it does not receive much attention in most current programs. A change of the attitude of teachers towards teaching the metric system is very important. Members of the American Chemical Society and especially those of the Division of Chemical Education should be in the forefront of teaching and promoting the metric system. The schools are the best and most important places for this. There is one more cogent reason why the United States should speedily join all other countries and use metric units: this is international communication. As a Spanish engineer wrote in a letter to Science some years ago: the whole world is speaking English as a first or second language so that we all have one international language for mutual understanding; in turn the United States should use the international language of science and measures which is the metric system. Further information about the metric system can he obtained from the Metric Association, Dr. D. V. Frost, President (Dartmouth University) or Louis F. Sokol, Secretary (624 N. Drury Lane, Arlington Heights, Illinois 60004). Attention is also directed to a bibliography of the metric system (84 pp.; 1196 ref.) by J. T . Rfilek and V. Antoine (1968) and supplement (September, 1969) which can be obtained from the Metric Association a t the above address. Rainer Fried
Department of Biochemistry Creighton University Medical School Omaha, Nebraska 68131
Volume 47, Number 6, June 1970 / 45 1
