

THE WEIGHING OF MARKET HAY. 95 
to a stop upon the scale and the weigher is then compelled to “ catch” 
_ the weight as the car passes slowly over it. Weights obtained in 
this manner are likely to be inaccurate, are not fair to anyone con- 
cerned, and should not be used as official weights. 
The correct way is to weigh the car standing still and uncoupled 
at both ends. As the scale track, when a car is on it, is lower than 
the track adjoining at each end, if the slack is taken up taut, espe- 
cially in a long string of cars, the weight indicated will be less than 
the actual weight. Conversely, in a long string, with no slack taken 
up, the weight indicated will be greater than the actual weight. 
Care must be taken also in weighing cars during a high wind, 
as the weight of a car may vary several hundred pounds between the 
highest and lowest pressure of the wind. 
Some railroads have installed automatic weighing devices at scales 
where considerable weighing is done, which greatly facilitate the 
weighing and guarantee correct weighing if properly operated. The 
device or recorder is attached to the end of the weight beam and 
eliminates the use of the poise weight. The movement of the beam, 
which is regulated by balance weights in the mechanism, causes a 
wheel upon which weight designations are set in type to revolve until 
the number indicating the weight of the load is in position to print 
the amount upon a ticket. 
Tripping levers are placed alongside the car rail at each end of the 
scale which indicate the passing of the car onto and off the scale and 
also operate the printing mechanism. Cars which are to be weighed 
are pushed upon the scale or rolled onto it from a slight incline or 
hump. A ticket is placed in proper position in the recorder mechan- 
ism. As the car passes clear of the first tripping device onto the 
scale, the beam comes to a balance automatically and the printing ar- 
rangement is released and stamps the weight in 100 pounds upon the 
ticket. As the car passes off the scale the second tripper is oper ated 
and-sets the weighing attachment for the next car. 
Tt is claimed that this weighing mechanism will weigh and record 
the weights accurately so long as the car does not pass over the 
scales at a speed greater than 5 miles an hour. It is necessary for 
cars to be free from each other, however, and unless the first car has 
passed the second tripping arrangement the following car can not be 
weighed. ' 
THE TARE WEIGHT. 
When cars are weighed by railroad companies the tare weights 
stenciled on the cars are usually used, as there is no opportunity to 
weigh the empty car. Railroad cars are weighed when put into serv- 
ice and usually after any extensive repairs have been made. New 
cars are also generally reweighed after they have been in service 
