'Two hands shoveling, two more taking off, and one at the barrow, constitute a gang of five persons who turn out from 30,000 to 35,000 per day of ten hours. As brick makers' days are from sun to sun, say twelve working hours per day, during the season, from 46 to 50,000 bricks, per day, may be made by a single machine. This is, however, by no means the most important feature in the invention.
'In the ordinary mode of making bricks, the manufacturer cannot begin operations for the season, until the spring has so far advanced that working in wet clay will no longer chill his moulders' hands. On the same account, he loses also morning hours, until the advance of summer enables his hands to put in the whole period of daylight. He loses, also, sometimes days together—from the entire stoppage of his operations in the rainy weather, which forbids the bricks being put out to dry. In making press brick, all these difficulties are obviated. As a theory, operations in this mode can go on throughout the entire winter, frost never extending into solid clay; but as a practical business, it can be conveniently carried on two months earlier and one month later than in the ordinary mode. Pressed brick, made by these machines, are also stronger than their competitive article, the last of equal hardness in burning, always giving way when struck by the pressed bricks, as I have witnessed. Indeed, it cannot be otherwise, the one being porous and the other as compact as the enormous pressure employed can make it.
'The machine, it must be apparent, offers peculiar advantages in turning out brick without occupying the ordinary brick yard space necessary for spreading wet brick out to dry. It affords great economy in time, owing to its operations being independent of frost or rains. To every new and thriving place commencing the making of bricks, it dispenses with the necessity of bringing skilful workmen from other places—in short, it enables every man to be his own brick-maker. Under these considerations, I anticipate an extensive sale of these machines, especially for places at a distance.'
Marble Saw Mills.
We are informed that a large mill for sawing marble is in course of erection at Brandon, Vt. The marble in that vicinity is principally of a beautiful white, and of a fine texture, though not very hard.
Railroad Locks.
It is reported that locks for elevating railroad trains, from one level to another, are coming into successful use in France. It appears to us to be much behind the age, since, by certain American inventions, an ordinary train may be elevated 100 feet in five minutes, by the engine alone.
The Vertical Propeller.
We have alluded to this subject in a former number, and now present one of the several plans which have been introduced within the present year, although we are not fully authorised to give the name of the inventor of this particular plan. We have preferred to represent the paddles and crank unconnected with an apparent vessel or section thereof, but must require the reader to suppose that the line A B is the level of the railing of the boat, and that the crank-shaft E projects from the side, while the crank-pivot governs the motion of the walking bar D E, and with it the paddles, which are supposed to be just now dipping in the surface of the water. It will be understood that the motion of the walking bar being circular, and that of the heads of the paddles being vertical and nearly rectilinear, the motion of the blades of the paddles must be elliptical, inclining to the horizontal; and that the position of the paddles is kept so nearly vertical that they will meet with less resistance in entering or leaving the water than those of a common paddle wheel, while the atmospheric resistance to be encountered thereby is much less. There appears no reasonable doubt that this plan might be made to succeed well on a larger scale, though it is very doubtful whether any of the steamboat proprietors can be persuaded to adopt it until it has been more thoroughly tested by experiment.