The counter at London, first called the Steelyard in a parliamentary petition of 142 2, claimed jurisdiction over the other factories in England.
Under Elizabeth, however, the English Merchant Adventurers could finally rejoice at the withdrawal of privileges from the Hanseatics and their concession to England, in return for the retention of the Steelyard, of a factory in Hamburg.
It consists of a steelyard mounted on a fulcrum; one arm carries at its extremity a heavy bob and pointer, the latter moving along a scale affixed to the stand and serving to indicate when the beam is in its standard position.
Before the end of the 16th century the privileges of the London Steelyard were suppressed by Elizabeth.
In 1853 they sold their common property, the London Steelyard; until 1866 they enlisted by special contract their military contingents for the German Confederation, and down to 1879 they had their own court of appeal at Lubeck.
The Hanseatic League, particularly, had numerous settlements of this kind, the earliest being the Steelyard at London, established in the 13th century.
Unequal-armed balances may be divided into (I) balances consisting of a single steelyard; (2) balances formed by combinations of unequal-armed levers and steelyards, such as platform machines, weighbridges, &c.
The ordinary way of using a steelyard is to bring it into a horizontal position by means of movable weights, and to infer the amount of the load from the positions of these.
The more elaborate ones are made either with a heavy travelling poise to measure the bulk of the load with a light travelling poise for the remainder, or else with a knife-edge at the end of the steelyard, on which loose weights are hung to measure the bulk of the load, the remainder being measured with a light travelling poise.
Then if Z be below the line joining X and H, the steelyard will be " accelerating "; i.e.
With the smallest excess of moment on the left-hand side of the fulcrum, the end C of the steelyard will rise with accelerating velocity till it is brought up by a stop of some sort; and with the smallest excess of moment on the right-hand side of the fulcrum, the end C of the steelyard will drop, and will descend with accelerating velocity till it is brought up by a similar stop. If Z be above the line XH, the steelyard is " vibrating "; i.e.
The principle is as follows: The weighing is effected by a steelyard with a sliding poise which is set to weigh a definite weight of the material, say I lb.
A rod, connected at its lower end with the steelyard, carries at its upper end a horizontal dividing knife, which cuts off the flow from the shoot when the steelyard kicks.
When the filled packet is removed, the steelyard resumes its original position, and the filling goes on automatically.
The automatic personal weighing machine found at most railway stations operates by means of a steelyard carrying a fixed weight on its long arm, the load on the platform being inferred from the position of the steelyard.
They are also used as trade computing machines, as in the case of the machine made by the Computing Scale Company, Dayton, Ohio, U.S.A. In this machine the goods to be priced are placed on the platform of a small platform machine whose steelyard is adjusted to balance exactly the weight of the platform, levers and connexions.
The rod which transmits the pull of the long body lever of the platform machine to the knifeedge at the end of the short arm of the steelyard is continued up - wards, and by a simple mechanical arrangement transmits to an upper steelyard any additional pull of the long body lever due to the weight of goods placed on the platform.
This upper steelyard is arranged as in fig 9, where A is the point where the pull of the long body lever due to the weight of the goods on the platform comes upon the steelyard; C is the fulcrum of the steelyard, which with the steelyard can be slid to and fro on the frame of the machine; and Q 8 s frl FIG.
The steelyard is exactly in balance when there is no weight on the platform and Q is at the zero end of its run, at 0.
If Q lb be the weight of the poise Q, the position of Q when the steelyard is exactly in balance is given by the equation I T: X q.d Q X OQ, or OQ =p X q X T -.
Thus to ascertain the value of goods on the platform of unknown weight at a given price per lb, it is only necessary to slide the steelyard till the weight acts at the division which represents the price per lb, and then to move the poise Q till the steelyard is in balance; the number of the division which defines the position of the poise Q will indicate the sum to be paid for the goods.
When the load on the platform is large, so that the value of the goods may be considerable, it is convenient to measure the larger part of the value by loose weights which, when hung at the end of the steelyard, represent each a certain money value, and the balance of the value is determined by the sliding poise Q.
The power is applied at the end of the long arm of the steelyard and multiplied by levers from loo to 500 times, so that the weights used are small and handy.
The platform and the load upon it are carried on four knife-edges, two of which, x 1 and x 2, are shown, and the load is transferred to the steelyard by the two levers shown, the upper one CD being known as the long body," and the lower, one EF as the " short body."
Gravity of the long body CD, and be the centre of gravity of the three vertical forces acting downwards at the points x i, and considered as weights collected at those points; then if be above the line z i y i it can be shown that this arrangement of the knife-edges of CD favours the" acceleration " principle, and is suited to act with and assist an " accelerating " steelyard, and similarly if the point h2 be above the line z 2 y 2 in the case of the short body EF.
When a platform machine is in true adjustment, and the loose weights which are intended to be hung at the end of the steelyard are correct and consistent among themselves, a good and new machine, whose capacity is 4 cwt., should not show a greater error than 4 oz.
In some cases they are made " self-recording " by the following arrangement: The steelyard is provided with a large and a small travelling poise.
Each of these poises carries a horizontal strip of metal, which is graduated and marked with raised figures corresponding to those on the steelyard itself.
Some weigh - bridges are arranged in a manner similar to that of the platform machines already described, but having the long body lever turned askew, so that the end of it projects considerably beyond the side of the weighbridge casing, and the pillar and steelyard which receive its pull are clear of the wagon on the platform.
In another arrangement two similar triangular levers take bearing on opposite sides of an intermediate lever which communicates their pressures to the steelyard; this is a very sound and simple arrangement for ordinary long weighbridges.
Such are coal platform machines for weighing out [[[Unequalarm Ed]] coal in sacks, the levers of which are arranged as in the ordinary platform machines, but for the sake of compactness the steelyard is returned back over the long body, and when loaded with the proper weight indicates the correct weight of the coal in the sack by its end Elevation.
The trucks or other receptacles containing the coal, &c., are drawn upon the platform of the machine, and the pull of the load is transferred by a vertical rod at the left-hand end of the machine to the knife-edge on the short arm of the steelyard, whose fulcrum is carried on bearings in the frame.
By the first part of this drop the movement of the poise is suddenly stopped, as will be explained below, and the travel of the poise along the steelyard, which measures the load on the platform, is recorded by the amount of rotation of the large spur wheel, and this is suitably shown on a dial in connexion with the wheel.
When the poise is at the zero end, and there is no load on the platform, the end of the steelyard is down, and has locked the ratchet wheel by means of the pawl; the shaft being thus locked, the sprocket wheels are stopped, the drum-shaft runs free by the friction clutch, and the two pulleys which are connected by the crossed band are running idle.
When the load to be weighed comes upon the platform, the end of the steelyard rises and unlocks the ratchet wheel through the pawl; the sprocket gearing is driven by the friction clutch, and drives the axle of the left-hand small pulley.
The mitre wheels come into operation and the poise is carried along till the end of the steelyard drops, and locks the ratchet by permission of the Controller of wheel.
By means of a horizontal rod the same drop of the steelyard also locks ne.
The weight, W, of the steelyard acting at its centre of gravity; G, the travelling poise; P, acting at M; and the weights, Q, hung on the knife-edge at Y.