were carried across the building from wall to wall, passing through holes in the walls, and were secured by nuts on the outside.  In this state they would have been sufficient to have prevented the further separation of the walls by the weight of the roof, but it was desirable to restore the walls to their original state by drawing them together.  This was effected in the following manner:  Alternate bars were heated by lamps fixed beneath them.  They expanded, and consequently the nuts, which were previously in contact with the walls, were no longer so.  The nuts were then screwed up so as to be again in close contact with the walls.  The lamps were withdrawn and the bars allowed to cool.  In cooling they gradually contracted and resumed their former dimensions; consequently the nuts, pressing against the walls, drew them together through a space equal to that through which they had been screwed up.  Meanwhile the intermediate bars were heated and expanded, and the nuts screwed up as before.  The lamps being again withdrawn, they contracted in cooling, and the walls were further drawn together.  This process was continually repeated, until at length the walls were restored to their perpendicular position.  The gallery may still be seen with the bars extending across it, and binding together its walls.—­Philadelphia Record and Guide.

LOSS OF POWER BY RADIATION OF HEAT.[3]

[Illustration:  The Martyrs Column, Naples, Italy.]

To him who holds the purse and pays for the coal consumed, it is of importance that between the energy of the burning fuel and the power developed by the engine there should be the least possible loss.  Every unit of heat radiated by boiler-pipe, cylinder or heater is absolute loss, and must come out of that purse.  In an electrical plant this matter is of great importance.  There is less opportunity to have results obscured.  There is, proportionally, a large possible loss between the coal on the grate and the far end of the cylinder, and this loss should be reduced to the minimum.  Is it not always the best economy to throw away as little as possible, to save from waste all that can be saved?  Is not the very reason far being, of the architect, the mechanical engineer, in fact of every man who is paid for his advice and direction, just this:  that he shall bring to bear upon the subject, and impart to his client honest knowledge concerning the various matters about which he is consulted?  That he shall keep abreast of the tide of discovery and improvement, and that upon these subjects he shall know, not trusting to mere hearsay or to unintelligent prejudice for his impressions.