measuring sixty-two feet long and twenty wide.  It is three feet in depth and draws seventeen inches of water.  It is driven entirely by air, Root’s blower No. 4 being used, the latter operated by an eight-horse-power engine.  The air is forced down a central shaft to the bottom, where it is deflected, and, being confined between keels, passes backward and upward, escaping at the stern through an orifice nineteen feet wide, so as to form a sort of air wedge between the boat and the surface of the water.  The force with which the air strikes the water is what propels it.  The boat has a speed of four miles an hour, but requires a thirty-five-horsepower engine to develop its full capabilities.  The patentee claims a great advantage in doing away with the heavy machinery of screws and side-wheels, and believes that the contrivance gives full results, in proportion to the power employed.  It is also contrived for backing and steering by air propulsion.  Owing to the slight disturbance which it causes to the water, it is thought to be very well adapted for work on canals without injury to the sides.—­Boston Journal.

* * * * *

HEAD LININGS OF PASSENGER CARS.

The veneer ceilings are considered as much superior to cloth as cloth was to the roof-ceiling.  They are remarkably chaste, and so solid and substantial that but little decoration is necessary to produce a pleasing effect.  The agreeable contrast between the natural grain of the wood and the deeper shade of the bands and mouldings is all that is necessary to harmonize with the other parts of the interiors of certain classes of cars—­smoking and dining cars, for example.  But in the case of parlor and dining-room cars, the decorations of these ceilings should be in keeping with the style of the cars, by giving such a character to the lines, curves, and colors, as will be suggestive of cheerfulness and life.  While these head linings are deserving of the highest commendation as an important improvement upon previous ones, they are still open to some objections.  One barrier to their general adoption is their increased cost.  It is true that superior quality implies higher prices, but when the prices exceed so much those of cloth linings, it is difficult to induce road managers to increase expenses by introducing the new linings, when the great object is to reduce expenses.  Another objection to wood linings is their liability to injury from heat and moisture, a liability which results from the way in which they are put together.  A heated roof or a leak swells the veneering, and in many cases takes it off in strips.  To obviate these objections, I have, during the past eighteen months, been experimenting with some materials that would be less affected by these causes, and at the same time make a handsome ceiling.  About a year ago I fitted up one car in this way, and it has proved a success.  The material used is heavy tar-board pressed into the form of the roof and strengthened by burlaps.  It is then grained and decorated in the usual manner, and when finished has the same appearance as the veneers, will wear as well, and can be finished at much less cost.—­D.D.  Robertson.