678 



Popular Science Monthly 



The Corrugated Wood Block for 

 Street Paving 



TH E corrugated 

 wood block 

 marks an important 

 advance in the manu- 

 facture of paving 

 materials. One side 

 and one end of each 

 block are corrugated 

 or grooved in the 

 direction parallel to 

 the grain by a spec- 

 ial machine. These 

 grooves immediate- 

 ly adjoin each other. 

 The dividing lines 

 are of almost knife- 

 like sharpness. 



The particular 

 advantage of cor- 



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PAVEMENT FILLER 



,t DEPTH 



CORRUGATED CREOSOTE BLOCK 



The corrugations auto- 

 matically provide the 

 space for the filler 



nigated block lies in the fact that the 

 blocks may be laid snugly together, course 

 on course and block on block, without fear 

 of displaced alinement due to expansion 

 from temperature or moisture. In laying 

 the ordinary block the workmen must 

 attempt to provide a space between 

 the courses and between the blocks in 

 the courses. 



With this newly invented block the 

 corrugations automatically provide 

 the necessary space for the pavement 

 filler to flow to the bottom of the 

 block, effectually sealing the pavement 

 against moisture. Under certain con- 

 ditions wood block has a tendency 

 to expand. When this con 

 dition exists with corru- 

 gated blocks, the knife-like 

 edges crush or bury them- 

 selves in the adjoining 

 blocks, relieving the pres- 

 sure at once. Each block 

 has its own expansion joint. 



Clearing a Crippled Car from 

 Railroad Tracks 



WHEN a car 

 breaks down 

 on a busy road, it is 

 of first importance to 

 clear it out of the 

 way so that traffic 

 may go on undis- 

 turbed. The car itself 

 can be repaired when 

 it reaches the barn, so 

 that the first prob- 

 lem is to get it there 

 as quickly as pos- 

 sible. For this pur- 

 pose, the master me- 

 chanic of a Western 

 traction company 

 has devised a piece 

 of apparatus which 

 can temporarily take 

 the place of a broken 

 axle on a car. The 

 apparatus is merely 

 an auxiliary truck 

 with small railroad wheels rigidly held 

 apart so that they properly fit into the rails. 

 When a car has broken down, an emer- 

 gency car equipped with a set of these 

 trucks is immediately sent out. The 

 crippled car is lifted up by heavy screw- 

 jacks at the end where it has broken down. 

 The auxiliary truck is then run underneath 

 the broken axle, the car wheels are fitted 

 into the frame, and the whole apparatus is 

 strongly fastened to the car by means of 

 heavy chains. The car then runs back to 

 the barn by its own power. 



The workmen drive the courses 

 snugly and place each corrugat- 

 ed block without having to 

 make calculations for expansion 



When the car breaks down, 

 an auxiliary truck with small 

 railroad wheels is run under 

 the broken axle to support it 



