EARL   AND  LOOMIS—STRENGTH OE BRICK MASONRY.           37

CONCLUSION.

The table shows, roughly, that the beams built as regular ma¬
sonry have a niodulus of rupture of about twice the tensile strength
of the mortar used. With the best construction we believe it may
be even three times the tensile strength of the mortar, as shown by
beams No. 4 and 7. When built as piers, with no interlocking ac¬
tion, the modulus of rupture is about the same as the tensile strength
of the mortar used.

The experiments on deflections with beam No, 4 while not
enough to draw any certain conclusion from, would seem to show
that brick masonry is elastic and that up to a certain point the de¬
formation is proportional to the stress applied.

The result of experiments in the past, while showing a certain
transverse strength, have not been definite or uniform enough to
furnish reliable conclusions. We believe we have shown that this
strength can be counted upon in designing.

While the nature of this subject does not permit of its being
carried in an experimental way as far as might be desired, without
considerable expense, we would suggest that much can yet be done
towards finding the strength actually obtained in brick buildings.
The tearing down or failure of such buildings aflfords an excellent
opportunity for this and it is to be hoped that experiment and obser¬
vation will be turned in this direction.
 

A BIG SIPHON.
 

By J. N. Chester, '91.   Constructing Engineer, New York City Suburban

Water Co.
 

The waiter recently had charge of the construction of a large
siphon, which on account of its unusual lift and great length may
be worfchy of description. This siphon has a length of 925 feet, and
its maximum lift of 23 feet is made with a head, or difference in
level of the water at the intake and outlet, of only 2 feet. So far
as ascertained these conditions are far more severe than those of any
siphon on record.

Mount Vernon, a city of 18,000 inhabitants, on Long Island
Sound, 14 miles northeast of the Grand Central Depot, New York
City, is furnished water by the New York City Suburbaii Water
Company.    Up to 1892 the source of supply was the Pelhamville res-