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satisfaction. I think a great deal may be done and much 
light thrown upon the subject by a careful and well con- 
ducted class of experiments ; in hollow tubes there is great 
scope, particularly as relates to varied diameters, thickness 
of metal, and the proportions of the upper to the lower 
diameters. Also an investigation into the proportions of 
the ancients, in order to ascertain whether the small rising 
from the lower base of the shaft is intended for beauty 
or strength : probably both qualities are included, and may 
be the result of experiment. In point of form you are 
aware that the symmetry varies in the different ages of the 
Egyptians, Greeks, and Romans, at any rate the swell ob- 
servable in the best proportioned columns of the antique are 
valuable as far as it prevents deflection and must add to the 
strength of the shaft. I speak from memory as regards the 
proportions, but I think it would be useful as well as inter- 
esting to ascertain the strongest form, and probably the 
diameter near the middle will be the nearest approach. 
The antique is of this form : — but you 
can easily ascertain these particulars in 
any work on architecture. 
Having completed the experiment on 
columns, the next business will be to 
prepare the papers for the Association. 
I have written a few pages introductory 
to the experiments on the transverse 
strains, but I think it will want re- 
modelling, as well as considerable 
additions. 
When I have the pleasure of your presence here in 
London it will be a good opportunity to get the papers 
printed. We could then read over the proofs and super- 
intend the press at the same time. What think you of 
this ? Will you write to Phillips and arrange it accord- 
ingly ? We shall never have a more fitting opportunity. 
