July 17, 1896.] 



SCIENCE. 



61 



mals before common fractions, as they are 

 virtually familiar with decimals when they 

 have learned their notation, and the transi- 

 tion to fractions of other denominations 

 than ten is more easy than the reverse. In 

 common life we are discarding vulgar 

 fractions, except the simplest, and using 

 decimals. 



The increasing use of multiples of ten in 

 place of the dozen and gross is another in- 

 dication of the Same disposition to gravitate 

 toward a decimal system. Vegetables are 

 now often sold in bunches of tens and fives, 

 and many small articles of dry goods are 

 put up in the same way. As this makes 

 the pricing of the articles so much simpler 

 it seems likely to prevail. 



Judging from present progress in the 

 United States, ' the pressure of business ' 

 and the necessity of simplification is forc- 

 ing the American people to a decimal divi- 

 sion of weights and measures. People will 

 use tenths in practice whether the govern- 

 ment favors it or not. The only question 

 is whether the units will be those of all the 

 world except England or a separate system. 

 If the metric system is not adopted it will 

 not be long before we shall be using mostly 

 tenths and hundreds of pounds, feet and 

 inches. While this would be better than 

 the present chaos, it would not be so good as 

 the metric system in which all the units are 

 in simple relations to one another. 



As for the objections raised against the 

 metric system on the ground of inconven- 

 ience, we know by experience with our deci- 

 mal coinage how groundless they are. The 

 most ignorant among us have no practical 

 difliculty with those divisions which appear 

 so unnatural to the English. Mr. Spencer 

 objects to the metric system on the ground 

 that ten is not divisible by three, and thinks 

 the present customs preferable on account 

 of ' the widow's thirds and in Parliamen- 

 tary Acts the two-thirds majority.' The il- 

 lustrations are unhappily chosen ; since the 



English pound is no better divisible by 

 three into shillings than the American dol- 

 lar into cents, and it is hard to see how the 

 adoption of a duodecimal system would in- 

 sure the division into thirds of a Parlia- 

 ment consisting of a varying number of 

 men. The question is often asked what is 

 a shopkeeper to do when a customer wants 

 a third of a kilogram. If such a case 

 should occur the shopkeeper need only pile 

 2's and I's of each denomination on his 

 scalepan until the weight was reached 

 within the limits of delicacj'' of his scales. 

 But what is he to do if asked for the third 

 of a pound ? If calculation in our present 

 system is as easy as claimed, he would in- 

 stantly perceive that he could get the 

 weight by laying on the scalepan five 

 ounces, five drams, nine and eleven ninety- 

 sixths grains. This also is a '■ makeshift 

 third.' 



The objection is also urged that the me- 

 tric system would not be in accordance 

 with our division of time. But since the 

 natural units of time, the day, the month 

 and the year are incommensurable no sj^s- 

 tem of numeration can agree with them. 

 As it is, our notation and our measures of 

 weight, length, area, volume and time 

 have no relation to each ofcher. With the 

 adoption of the metric system our notation 

 and all our measures except time will 

 agree. The value of the Centigr.ade ther- 

 mometer need not be discussed, since it is 

 not a part of the metric system, and the 

 adoption of that system does not carry with 

 it the Centigrade thermometer. As there 

 is no relation between the boiling and 

 freezing points of water at an arbitrary at- 

 mospheric pressure and any system of 

 weights and measures, the Fahrenheit scale 

 is just as well suited to the metric system 

 as any other. It should be noticed, how- 

 ever, that in both scales the fractions of a 

 degree are reported in tenths, not in halves 

 quarters and thirds. A thermometer scale 



