ANNUAL ADDRESS OF THE PRESIDENT. 
XLIII 
accurately than either of them can be determined in terms of the 
supposed unit, three fundamental units are preferable to two. 
The Chaldeans, Babylonians, Persians, Greeks, and Romans all 
seem to have had systems of weights and measures based upon toler¬ 
ably definite standards, but after the decline of the Roman Empire 
these standards seem to have been forgotten, and in the beginning 
of the sixteenth century the human body had so far become the 
standard of measurement that the units in common use, as for ex¬ 
ample, the foot, palm, etc., were frequently taken directly from it. 
The complete table of measures of length was then as follows : the 
breadth (not the length) of four barley corns make a digit, or finger 
breadth; four digits make a palm, (measured across the middle 
joints of the fingers;) four palms are one foot; a foot and a half 
is a cubit; ten palms, or two feet and a half, are a step; two steps, 
or five feet, are a pace; ten feet are a perch ; one hundred and 
twenty-five paces are an Italic stadium ; eight stadia, or one thousand 
paces, are an Italic mile ; four Italic miles, are a German mile ; and 
five Italic miles are a Swiss mile. It was then the practice to fur¬ 
nish standards of length in books by printing in them lines a foot or 
a palm long, according to the size of the page, and from these and 
other data it appears that the foot then used on the continent of 
Europe had a length of about ten English inches. 
In England the first attempts at scientific accuracy in matters of 
measurement date from the beginning of the seventeenth century, 
when John Greaves, who must be considered as the earliest of the 
scientific metrologists, directed attention to the difference between the 
Roman and English foot by tolerably accurate determinations of 
the former, and also attempted the investigation of the Roman 
weights. He was followed by Dr. Edward Bernard, who wrote a 
treatise on ancient weights and measures about 1685, and towards 
the end of the century the measurements of the length of a degree 
by Picard and J. D. Cassini awakened the attention of the French 
to the importance of rigorously exact standards. In considering 
the progress of science with respect to standards of length we may 
safely confine our inquiries to the English yard and the French 
toise and meter, for during the last two hundred years they have 
been almost the only standards adopted in scientific operations. 
The English measures of length have come down from the Saxons, 
but the oldest standards now existing are the Exchequer yards of 
