When we consider that since the post-drilling machine first made its appearance, there have been added Blasdell’s quick return, the automatic feed, belt-driven spindles, back gears placed where they ought to be, with many minor improvements, it is not safe to assume that the end has been reached; and when we consider that as a piece of machine designing, considered in an artistic sense entirely, the Bement post drill is the finest the world ever saw (the Porter-Allen engine not excepted, which is saying a good deal), is it not strange that of all mechanical designs none other has taken on such outrageous forms as this?

One thing that would seem to be desirable, and that ordinary skill might devise, is some sort of snap clutch by which the main spindle could be stopped instantly by touching a trigger with the foot; many drills and accidents would be saved thereby.  Of the many special devices I have seen for use on a drilling machine, one used by Mr. Lipe might be made of universal use.  It is in the form of a bracket or knee adjustably attached to the post, which has in its upper surface a V into which round pieces of almost any size can be fastened, so that the drill will pass through it diametrically.  It is not only useful in making holes through round bars, but straight through bosses and collars as well.

The radial drill has got so it points its nose in all directions but skyward, but whether in its best form is not certain.  The handle of the belt shipper, in none that I have seen, follows around within reach of the drill as conveniently as one would like.

As the one suggestion I have to make in regard to the shaping machine best illustrates the subject of maintaining true wearing surfaces, I will leave it until I reach that part of my paper.

(To be continued.)

* * * * *

THE MECHANICS OF A LIQUID.

A liquid comes in handy sometimes in measuring the volume of a substance where the length, breadth, and thickness is difficult to get at.  It is a very simple operation, only requiring the material to be plunged under water and measure the amount of displacement by giving close attention to the overflow.  It is a process that was first brought into use in the days when jewelers and silversmiths were inclined to be a little dishonest and to make the most of their earnings out of the rule of their country.  If we remember rightly, the voice of some one crying “Eureka” was heard about that time from somebody who had been taking a bath up in the country some two miles from home.  Tradition would have us believe that the inventor left for the patent office long before his bathing exercises were half through with, and that he did the most of his traveling at a lively rate while on foot, but it is more reasonable to suppose that bath tubs were in use in those days, and that he noticed, as every good philosopher should, that his bathing solution was running over the edge of the tub as fast as his body sunk below the surface.  Taking to the heels is something that we hear of even at this late day.