190 POPULAR SCIENCE MONTHLY. 



You are right. Tlie arrangement was practically dictated by Nature. 

 The division of the circle was the outcome of the Chaldean division of the 

 heavens to fit their calendar: a degree heing, within l-60th, equivalent to a 

 day's apparent motion of the Sun on the ecliptic. And that reminds me 

 that I do not find in youi* scheme any proposal for redivision of the year. 

 Why do you not make 10 months instead of 12 ? 



A partial decimalization of the calendar was attempted at the time of the 

 French Revolution ; a week of ten days was appointed, but the jilan failed. 

 Of coui-se, the 365 days of the year do not admit of division into tenths ; or, 

 if ten months were made, there could he no tenths of these. Moreover, 

 even were it otherwise, certain deeply-rooted customs stand in the way. 

 Many trading transactions, especially the letting of houses and the hiring 

 of assistants, have brought the quarter-year into such constant use that it 

 would be very difficult to introduce a redivision of the year into tenths. 



Just so; and it occurs to me that there is a deeper reason. Ignoring the 

 slight ellipticity of the earth's orbit, a quarter of a year is the period in 

 which the Earth describes a fourth of its annual journey round the Sun, 

 and the seasons are thus determined — the interval between the shortest day 

 and the vernal equinox, between that and the longest day, and so on with 

 the other divisions. 



The order of Nature is doubtless against us here. 



It is against you here in a double way. Not only the behavior of the 

 Earth, but also the behavior of the Moon conflicts with your scheme. By 

 an astronomical accident it happens that there are 12 full moons or ap- 

 proximately 12 synodic lunations in the year ; and this, first recognized by 

 the Chaldeans, originated the 12-month calendar, which civilized peoples in 

 general have adopted after compromising the disagreements in one or other 

 way. But there is another division of time in which you are not so ob- 

 viously thus restrained. You have not, so far as I see, proposed to sub- 

 stitute 10 hours for 12, or to make the day and night 20 hours instead of 24. 

 Why not ? 



Centuries ago it might have been practicable to do this; but now that 

 timekeepers "have become universal we could not make such a redivision. 

 We might get all the church clocks altered, but people would refuse to re- 

 place their old watches by new ones. 



I fancy conservatism will be too strong for you in another case — that of 

 the compass. The divisions of this are, like many other sets of divisions, 

 made by halving and re-halving and again halving until 32 points are ob- 

 tained. Is it that the habits of sailors are so fixed as to make hopeless the 

 adoption of decimal divisions ? 



Another I'eason has prevented — the natural relation of the cardinal 

 points. The intervals included between them are necessarily four right 

 angles, and this precludes a division into tenths. 



Just so. Here, as before, Nature is against you. The quadrant results 

 from space-relations which are unchangeable and necessarily impose, in this 

 as in other cases, division into quarters. Nature's lead has been followed 

 by mankind in various ways. Beyond the quai'ter of a year we have the 

 moon's four quarters. The quarter of an hour is a familiar division, and 

 also the quarter of a mile. Though the yard is divided into feet and inches, 

 yet in every draper's shop yards are measured out in halves, quarters, 

 eighths, and sixteenths or nails. Then we have a wine merchant's quarter- 



