and a task to a comfort. Housings of the hollow box section furnish an
excellent place for the counterweights.

The moving head, which is not expected to move while under pressure,
seems to have settled into one form, and when hooked over a square
ledge at the top, a pretty satisfactory form, too. But in other
machines built in the form of planing machines, in which the head is
traversed while cutting, as is the case with the profiling machine,
the planer head form is not right. Both the propelling screw, or
whatever gives the side motion, should be as low down as possible, as
should also be the guide.

There is a principle underlying the Sellers method of driving a planer
table that may be utilized in many ways. The endurance goes far beyond
any man's original expectations, and the explanation, very likely,
lies in the fact that the point of contact is always changing. To
apply the same principle to a common worm gear it is only necessary to
use a worm in a plain spur gear, with the teeth cut at an angle the
wrong way, and set the worm shaft at an angle double the amount,
rather than at 90°. Such a worm gear will, I fancy, outwear a dozen of
the scientific sort. It would likely be found a convenience to have
the head of a planing machine traverse by a handle or crank attached
to itself, so it could be operated like the slide rest of a lathe,
rather than as is now the case from the end of the cross head. The
principle should be to have things convenient, even at an additional
cost. Anything more than a single motion to lock the cross head to the
housing or stanchions should not be countenanced in small planers at
least. Many of the inferior machines show marked improvements over the
better sorts, so far as handiness goes, while there is nothing to
hinder the handy from being good and the good handy.