The constructors consider the power developed by these engines very
moderate, on account of the low piston speed specified in this
particular case. In some small and light engines by the same makers
the piston speed is as high as 1000 ft. per minute. The engines now
illustrated form an interesting example of special designing, and
Messrs. Ahrbecker, Son, and Hamkens deserve much credit for the manner
in which the work has been turned out, the construction of such light
engines involving many practical difficulties,--_Engineering._

* * * * *

Mount Baker, Washington Territory, has shown slight symptoms of volcanic
activity for several years. An unmistakable eruption is now in progress.

* * * * *




COMPLETE PREVENTION OF INCRUSTATION IN BOILERS.


The chemical factory, Eisenbuettel, near Braunschweig, distributes the
following circular: "The principal generators of incrustation in boilers
are gypsum and the so-called bicarbonates of calcium and magnesium. If
these can be taken put of the water, before it enters the boiler, the
formation of incrustation is made impossible; all disturbances and
troubles, derived from these incrustations, are done away with, and
besides this, a considerable saving of fuel is possible, as clear iron
will conduct heat quicker than that which is covered with incrustation."