the side of the rectangle. Thus, the nearer the
support a strip parallel to that support is located, the less load it
can take, for the reason that it cannot deflect as much as the middle
strip. In the oblong slab the condition imposed is equal deflection of
two strips of unequal span intersecting at the middle of the slab, as
well as diminished deflection of the parallel strips.

In this method of treating the rectangular slab, the concrete in tension
is not considered to be of any value, as is the case in all accepted
methods.

Some years ago the writer tested a number of slabs in a building, with a
load of 250 lb. per sq. ft. These slabs were 3 in. thick and had a clear
span of 44 in. between beams. They were totally without reinforcement.
Some had cracked from shrinkage, the cracks running through them and
practically the full length of the beams. They all carried this load
without any apparent distress. If these slabs had been reinforced with
some special reinforcement of very small cross-section, the strength
which was manifestly in the concrete itself, might have been made to
appear to be in the reinforcement. Magic properties could be thus
conjured up for some special brand of reinforcement. An energetic
proprietor could capitalize tension in concrete in this way and "prove"
by tests his claims to the magic properties of his reinforcement.

To say that Poisson's ratio has anything to do with the reinforcement of
a slab is to consider the tensile strength of concrete as having a
positive value in the bottom of that slab. It means to reinforce for the
stretch in the concrete and not for the tensile stress. If the tensile
strength of concrete is not accepted as an element in the strength of a
slab having one-way reinforcement, why should it be accepted in one
having reinforcement in two or more directions? The tensile strength of
concrete in a slab of any kind is of course real, when the slab is
without cracks; it has a large influence in the deflection; but what
about a slab that is cracked from shrinkage or otherwise?

Mr. Turner dodges the issue in the matter of stirrups by stating that
they were not correctly placed in the tests made at the University of
Illinois. He cites the Hennebique system as a correct sample. This
system, as the writer finds it, has some rods bent up toward the support
and anchored over it to some extent, or run into the next span. Then
stirrups are added. There could be no objection t