418 



Popular Science Monthly 



A Movable Storehouse Elevator 



IN many industries which require the 

 storage and removal of heavy bales, 

 boxes or casks the employment of sta- 

 tionary elevators is impracticable. This 

 is the case in tobacco warehouses, in 

 chemical factories and in storehouses for 

 various raw materials, contained in pack- 



Boxes and bales for storage are easily 



handled by two men with this simple 



movable elevator 



ages half a ton in weight and a cubic 

 yard in bulk, must be handled. As the 

 bales are usually piled up four deep, the 

 ""Nork of storage, if done by hand labor, 

 as very fatiguing. 



The Zeitsclirift des Vereins deutscher 

 Jncjenieure says that a movable elevator 

 has been devised by \V. Dahlheim, which 

 has given satisfaction in the establish- 

 ments that have already adopted it. The 

 apparatus consists of a wrought-iron 

 skeleton tower having an inclined front, 

 which forms the runway for the plat- 

 form on which the load is placed. The 

 loaded platform is hoisted by means of 

 a hand-winch, so constructed that the 

 platform remains stationary when the 

 handle is released and descends gently 

 with uniform speed when the handle is 

 pressed backward. There are no separ- 

 ate brakes or catches to operate and ev- 

 ervthing is done with the winch handle. 

 The work is so light that one man can 



raise an average load of 500 pounds to 

 a height of twelve feet in one minute. 



The elevator is mounted on two large 

 wheels, at the back, and two small steer- 

 ing wheels in front. When it is to be 

 moved to a distant part of the establish- 

 ment, it is tipped backward on its large 

 wheels and moved like a hand truck. 

 The loaded elevator can be tipped with- 

 out disturbing the load and can be moved 

 through low doorways, while its small 

 width (about thirty inches), allows it to 

 traverse narrow passages. The vertical 

 back of the elevator may be constructed 

 in the form of a ladder, by which the 

 pile of goods can be climbed. The floor 

 of the platform is composed of a smooth 

 iron plate, for bales, or a number of ' 

 small rollers, for boxes. It can be load- 

 ed and unloaded either from the front 

 or the side. 



The field of this device is not restrict- 

 ed to storehouses. It may be utilized in 

 the erection of buildings, for loading 

 heavy articles on trucks or railway cars, 

 and in various other ways. Its economy 

 in operation is evident from the fact 

 that for average loads it requires the 

 service of only three men — one to load, 

 one to unload, and one to hoist. 



Why Do We Have Two Eyes? 



BECAUSE we have two eyes the things 

 we see seem solid and not flat, with 

 the result that we can judge their distance 

 from us with fair correctness. Look 

 through a window at a house across the 

 street with one eye closed and then with 

 the other eye closed. The bars of the win- 

 dow frame will cut across the opposite 

 house in different places. The two fields 

 seen with the eyes separately although in 

 the main alike, differ. When you look at 

 the house with both eyes open the two 

 fields seen by the two eyes are combined 

 and the house across the street assumes 

 depth and relief. Although we see a house 

 with each eye we see only one house with 

 both eyes. This makes the stereoscope 

 possible — an instrument so designed that 

 the two eyes are made to converge on a 

 single point and yet to see two different 

 pictures. If these two pictures repre- 

 sent a chair as it would appear to the 

 right and left eyes respectively, they 

 are perceived as one solid object. 



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