o stirrups if, apart
from them, the construction were made adequate, except that expense is
added thereby. Mr. Turner cannot deny that stirrups are very commonly
used just as they were placed in the tests made at the University of
Illinois. It is the common practice and the prevailing logic in the
literature of the subject which the writer condemns.

Mr. Thacher says of the first point:

"At the point where the first rod is bent up, the stress in this
rod runs out. The other rods are sufficient to take the horizontal
stress, and the bent-up portion provides only for the vertical and
diagonal shearing stresses in the concrete."

If the stress runs out, by what does that rod, in the bent portion, take
shear? Could it be severed at the bend, and still perform its office?
The writer can conceive of an inclined rod taking the shear of a beam if
it were anchored at each end, or long enough somehow to have a grip in
the concrete from the centroid of compression up and from the center of
the steel down. This latter is a practical impossibility. A rod curved
up from the bottom reinforcement and curved to a horizontal position and
run to the support with anchorage, would take the shear of a beam. As to
the stress running out of a rod at the point where it is bent up, this
will hardly stand the test of analysis in the majority of cases. On
account of the parabolic variation of stress in a beam, there should be
double the length necessary for the full grip of a rod in the space from
the center to the end of a beam. If 50 diameters are needed for this
grip, the whole span should then be not less than four times 50, or 200
diameters of the rod. For the same reason the rod between these bends
should be at least 200 diameters in length. Often the reinforcing rods
are equal to or more than one-two-hundredth of the span in diameter, and
therefore need the full length of the span for grip.

Mr. Thacher states that Rod 3 provides for the shear. He fails to answer
the argument that this rod is not anchored over the support to take the
shear. Would he, in a queen-post truss, attach the hog-rod to the beam
some distance out from the support and thus throw the bending and shear
back into the very beam which this rod is intended to relieve of bending
and shear? Yet this is just what Rod 3 would do, if it were long enough
to be anchored for the shear, which it seldom is; hence it cannot even
perform this function. If Rod 3