ON THE WEIGHTS AND MEASURES USED IN PHARMACY. 229 
ship to oue another; now that the former has become a half-sovereign it has 
ceased to be distinctively a decimal coin, and the florin has been introduced with 
the view of making the pound a unit on a decimal scale. 
In lineal measures, where the yard is almost exclusively used for trade pur¬ 
poses, we have similar evidence of the preference for binal division. The yard 
consisting of 3 feet or 36 inches, affords facility for the use of ternary fractions, 
such as g-, ^ or but, instead of these, in actual use we find i, |, and ; 
also the inch, which consists of 3 barleycorns or 12 lines, is not thus divided for 
actual use, but again we find the useful fractions L I, -§•, and -i-. 
In measures of capacity we have dry measure where the number 4 occurs four 
times as a factor, 2 occurs four times, and 5 only once. Wine measure has 4 oc¬ 
curring twice and 2 twice, but no number representing the decimal scale. Ale 
measure has 4 twice, 2 five times, 3 once, and 9 once, but no number repre¬ 
senting the decimal scale. 
In weights we have—troy, with the’'numbers 24, 20, and 12 ; apothecaries’,- 
with 20, 3, 8 , and 12; avoirdupois, with 16, 16, 14, 2, 4, and 20. Here we 
find “ 20 ” counting three times for the decimal scale; we have 24, 12, 3, and 
12, for the duodecimal ; and 8 , 16, 16, 2, and 4, for the octavial. 
Looking to pharmaceutical practices for evidence regarding the comparative 
utility of decimal or octavial scales, we find a general preference for the latter. 
Concentrated infusions and decoctions are made so that 1 part equals 8 of the 
normal strength. The great majority of bottles used for dispensing, etc., are 
founded upon octavial numbers of ounces. 1, 2, 4, 6 , 8 , 12, and 16, are the 
current sizes. 20 ounces are not frequently used, 10 ounces still more rarely, and 
5 ounces quite unknown. Looking at the posological table, in 36 cases taken at 
random, the minimum dose was to the maximum— 
In 11 cases as 
. . . . 1 to 2. 
In 10 „ 
. . . . 1 to 3. 
In 2 „ 
. . . . 1 to 4. 
In no case as 
. . . . 1 to 5. 
In 2 cases as 
. . . . 1 to 6. 
In 3 „ 
. . . . 2 to 3. 
In 8 „ 
. . . . 3 to 4. 
Thus there are 21 instances in which the octavial scale would most readily 
meet the wants of the case; 15 in which duodecimal would have the advantage ; 
but no instance in favour of the decimal,—no doubt, because the decimal scale 
does not so readily express these simple relationships. 
Turning to Thompson’s ‘ Conspectus , 1 we find a table of doses for patients of 
different ages, founded upon the full dose for an adult; thus :— 
Age in years 1 2 3 4 7 14 20 21 
DndP _i_ l A ± ± jl 2 ^ 
Supposing the full dose to be a unit of a quantity divided duodecimally, all 
these fractions would be obtained in the simplest possible manner : had the unit 
been divisible octavially, the fractions -j, and \ would have been obtained 
without dividing the next smaller grade of quantity ; had it been decimally 
divided, the \ is the only case in which the smaller grade would not be again 
divided ; the involving two lower grades, and the £ involving three lower 
grades. If the full dose were a multiple of the quantity at first supposed, the 
duodecimal scale would retain the good qualities it at first exhibited; and the 
other two scales would improve ; thus if the full dose were 3, 6 , or 9, the octa¬ 
vial or decimal would supply all the required fractions both accurately and 
readily; but if the full dose were 5 , the octavial scale would hold its original 
quality, and the decimal would be one step worse, in consequence of the hall 
