606 



Popular Science Monthly 



Dissecting a Rubber Plant to 

 Make It Grow 



TO transplant rubber plants success- 

 fully requires careful work on the 

 part of the inexperienced horticulturist. 

 The rubber leaf 

 should be cut off 

 with a part of the 

 plant attached 

 to the leaf stem, as 

 the accompanying 

 illustrations show. 

 The branch is so 

 important that 

 without it the leaf 

 will soon wither 

 and die. The next 

 operation is to fold 

 up the leaf care- 

 fully and to wrap 

 it securely with a piece of 

 string. The plant can now be 

 planted in wet sand in a hot- 

 house or placed under a bell 

 jar in the home. The leaf is 

 folded and tied so that the 

 sun will not absorb the mois- 

 ture from its delicate struc- 

 ture. This moisture, in turn, 

 feeds the stem and branch of 

 the plant until they are able 

 to draw their own moisture 

 soil. 



Cold Rolled Steel and Cold 

 Drawn Steel 



ALMOST every person in the me- 

 L chanical trades is familiar with steel 

 that is smooth and has a bright finish. 

 This steel comes in bars, rolls and shafts, 

 and most of us call it "cold rolled steel" 

 or "cold drawn steel." As a matter of 

 fact there is a wide difference between the 

 two, in the process of making, in the 

 nature of the steel, and in its use. To be 

 strictly correct and to avoid mistakes, 

 which may be costly, these differences 

 should be carefully noted. 



Cold rolled steel is, as its nature im- 

 plif's, rolled cold under great j)ressure, the 

 material used for the purpose being hot 

 rolled (black) stock. The machine which 

 does this work is called a rolling mill, and 

 consists of a pair of heavy, hard, and 

 highly polished steel rolls mounted in a 



massive frame and suitably driven. The 

 sheet or strip is passed between the rolls, 

 which impart the smooth finish and exact 

 size and shape, whether rectangular, 

 square, round or otherwise. Due to the 

 great pressure, the action of the rolling is 

 also one of squeez- 

 ing, and the stock 

 comes out thinner, 

 wider and longer 

 than when it went 

 into the rolls, and 

 with a rounded 

 edge, which re- 

 tains the black fin- 

 ish of the original. 

 Cold rolled steel 

 may be obtained in 

 "flats" 

 and in 

 strips in 

 a great 

 variety 

 of sizes 

 and in 

 thick- 

 nesses 

 of from 

 .002 in. 

 up. It is 

 relative- 

 ly soft 



and is used mostly for bending and 

 stamping purposes where a steel of 

 accurate thickness, bright finish, and easy 

 working qualities is desired. The thin- 

 ner and narrower stock may be obtained 

 in coils or rolls for use on automatic 

 machines that -.vork from a continuous 

 piece. Cold rolled steel is used extensive- 

 ly for drawing operations ; that is, for 

 the making of caps, cups, covers and 

 shells. 



Cold drawn steel is finished by an 

 entirely different process. It is this 

 process that gives us shafting, bars, rods 

 and keys, smooth, bright, strong and very 

 accurate. To obtain these desirable 

 qualities a bar of hot rolled steel, slightly 

 larger than the finished size, is run 

 through a machine known as a draw 

 bench, which has a highly polished, heavy 

 and hardened steel die with an opening 

 the exact size of the finished bar. By 

 means of a powerful chain and gripping 

 apparatus, the bar is pulled or drawn 

 through the die. 



Carefully handling the rubber plant for trans- 

 planting. The folding prevents evaporation 



from the 



