r could employ "and thrive under." It was found that the
worker's resistance of fatigue in lifting and carrying the load depended,
not on the amount of strength in terms of horse-power which he was
obliged to exert to elevate and sustain the load, but on the proportion
of his day spent in rest. For instance, a pig-iron handler, lifting and
carrying pigs weighing 92 pounds each, could lift and carry 47 tons of
iron in a day without undue fatigue if fifty-seven per cent of his
working hours were spent in rest, and forty-three per cent were spent in
work. If he lifted and put in place a number of pigs amounting to half
that tonnage, he might work without undue fatigue for a greater part of
the day. Under a certain far lighter load he could work without fatigue
all day long, with no rest whatever.

With accurate time-study as a basis, the "quickest time" for each job is
at all times in plain sight of both employers and workmen, and is reached
with accuracy, precision, and speed.[46]

OPERATION--WHEELBARROW EXCAVATION. Date, March 10, 189__

KEY:
A: Op.
B: Time
C: Av.
D: No. Shov.
E: Total time min.
F: Total picking min.
G: Total shoveling and wheeling min.
H: Times per barrow min.
I: No obs
J: Times per barrow min.
K: Time per pc. per shovel min.
L: No. shovels per barrow min.
M: Time wheeling 100 ft. min.

|A| B | C | D |A| B | C | D |A | B |C | D |A |B |C
--------------------+-+----+----+---+-+-----+-----+---+--+----+--+---+--+--+-
Department-- | | | | | | | | | | | | | | |
Construction |a|1.37|1.37|15 |a|1.12 |1.12 |12 |a'|1.86| |11 | | |
Men--Mike Flaherty |b|1.56|0.19| |b|1.39 |0.27 | |a'|1.81| |13 | | |
|c|1.82|0.26| |c|1.58 |0.19 | |a'|2.14| |16 | | |
Materials--Sand | | | | | | | | | | | | | | |
requiring no pick |d|1.97|0.15| |d|1.70 |0.12 | |a'|1.98| |14 | | |
Materials--Hard | | | | | | | | | | | | | | |
clay in bank |e|1.97|0.15| |e|1.92 |0.22 | | | | | | | |
Implements--No. 3 | | | | | | | | | | | | | | |
shovel; | | | | | | | | | | | | | | |
Contractors' | | | | | | | | | | | | | | |
wooden | | | | | | | | | | | | | | |
wheelbarrow |f|2.36|0.09| |f|2.36 |0.