MECHANICS AND USEFUL ARTS. 



The plowing we saw was respectably though roughly done, but there was 

 one point really performed the furrows were well turned. If a steam cul- 

 tivator can invert the soil thoroughly and cheaply, we may put up with a 

 little imperfection in the straightness of cutting and evenness of laying. The 

 method of anchoring the pulleys, and the arrangement of the pulleys and 

 ropes, is veiy ingenious, and can hardly be explained with brevity. The 

 anchorage consists of a plate or plow, a few feet in length, and eight inches 

 only in depth ; this can be easily drawn forward in the ground without the 

 trouble of digging holes, taking up, setting down again, etc., and yet it pre- 

 sents a sufficient resistance sideways to the pull of the ropes. A wheel, pinion, 

 and crank, on each anchor is used to draw it by means of a rope toward a 

 fixed post, when it is required to be shifted. The arrangement of the ropes 

 about the anchored pulleys is like that of the chains in a traveling crane, the 

 anchorage being shifted forward at intervals without altering the length of the 

 rope. The plows are not rigidly attached to the traveling frame, but are 

 hung by short iron beams, which form levers, having a slight degree of play 

 up and down. There are four plows two before and two behind the car- 

 riage, pointing opposite ways, a neat lever movement Ming two out of work 

 and dropping the other pair of plows in; so that the machine can plow both 

 ways without having to turn round at the land's end." 



IMPROVEMENTS liST THE MAXUTACTirRE OF STEEL. 



An important movement has been made in Eockaway, Morris County, 

 New Jersey, for the manufacture of cast-steel directly from the ore, without 

 the old process of converting the ore into iron and baking this iron into steel 

 before converting it into cast-steel. The idea is not a new one of making 

 steel directly from the ore, but it has been deemed impossible to produce a 

 uniform and cheap product. Improvements have, however, been recently made 

 by Dr. Smith, of Rochester, and a company has been formed for practical 

 working on a large scale. 



The process of converting the iron-ore into steel resolves itself into a se- 

 ries of means to make the ore as pure as possible without the expense of 

 smelting. For this purpose the best ore is selected to start with, this is 

 stamped and ground very fine, and after this it is run through magnetic ma- 

 chines, washed thoroughly, etc. After being dried, it is baked hi a manner 

 very similar to the ordinary way of baking bar-iron into steel. This is merely 

 a brief outline of the process by which they expect to escape much of the 

 drudgery and expense attendant on the old method. New York Tribune. 



RULE FOB CALCTJLATrNrG THE WEIGHT OF A CASTING FROM 

 THE WEIGHT OF ITS PATTERN. 



It is evident that the weight of a casting stands in the same proportion to 

 the weight of its pattern as the specific gravity of the former to that of the 

 latter, allowing, at the same tune, for the shrinking, i. e., contracting of the 

 casting in cooling. The following data are taken from an article of Professor 



