bad? One of the
most important and one of the first things in the construction of a
building is the foundation, and the laws which govern its construction
can be stated in a breath, and ought to be understood by every one.
Assuming the ground upon which a building is to be built to be of
uniform density, _the width_ of the foundation should be in proportion
to the load, the foundation should taper equally on each side, and the
center of the foundation should be under the center of pressure. In
other words, it is as fatal to success to have too much foundation
under the light load as it is too little under a heavy one.
Cannot we analyze causes and effects, cost and requirements, so as to
formulate some simple laws similar to the above by which we shall be
able to determine what is a good and what a bad arrangement of
machinery, foundation, framing or supports? A vast amount of work is
expended to make machines true, and the machines, or a large majority
of them, are expected to produce true work of some kind in turn. Then,
if this be admitted, cannot the following law be established, that
every machine should be so designed and constructed that when once
made true it will so remain, regardless of wear and all external
influences to which it is liable to be subjected? One tool maker says
that it is right, and another that it cannot be done. No matter
whether it can or cannot, is it not the thing wanted, and if so, is it
not an object worth striving for? One tool maker says that all machine
tools, engines, and machinery should set on solid stone foundations.
Should they?
They do not always, for in substantial Philadelphia some machine tools
used by machine builders stand upon second floors, or, perhaps, higher
up. And of these machine tools none, or few at least, except those
mounted upon a single pedestal, are free from detrimental torsion
where the floor upon which they rest is distorted by unequal loading.
But, to first consider those of such magnitude as to render it
absolutely necessary to erect them--not rest them--on masonry, is due
consideration always taken to arrange an unequal foundation to support
the unequal loads?--and they cannot be expected to remain true if not.
When one has the good fortune to have a machine to design of such
extent that the masonry becomes the main part of it, what part of the
glory does he give to the mason? Is the masonry part of it always
satisfactory, and is not this resorting to
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