PERIODICAL LITERATURE 827 



Boulevard. The blocks in this pavement were treated with 20 pounds 

 of a creosote-coal tar solution per cubic foot. Extreme bleeding made 

 the street impassable during the hot summer months in 1910, 191 1, and 

 1912. In 1917 the "pop-ups" caused by excessive expansion became so 

 numerous that the street became dangerous for traffic. This trouble is 

 increasing every year. 



Destruction of Wood Block Pavement Due to the Use of Tar in the Creosote 

 Oil. P. C. Reilly, Municipal Engineering, LIV, May, 1918, pp. 183. 



In driving logs of spruce and balsam fir a cer- 

 Water Absorption tain number are invariably lost due to waterlog- 

 of gi"g- The Forest Products Laboratories of Can- 



Frozen Wood ada have recently concluded a laboratory study 

 to determine whether frozen logs will absorb 

 more water and be more likely to sink than logs which are thawed be- 

 fore they go into the water. The conclusions drawn from the study 

 are as follows : Frozen wood put into water will, until it has thawed, 

 absorb more moisture than wood which is thawed before it goes into 

 the water ; but after the frozen wood has thawed in the water it will 

 absorb less moisture than the wood which was not frozen when it was 

 put in the water. The very small difference in the total moisture con- 

 tent indicates that whether or not logs are frozen when put into water 

 has little effect upon the subsequent sinking of the logs. 



B. L. G. 



Absorption of Water by Frozen Green Wood as Compared zcith that of the 

 Wet Green Wood. Pulp and Paper Magazine of Canada, XVI, April 25, 1918, pp. 

 379- 



During recent years the production of wild 



Rubber rubber has markedly decreased, from 70,410 tons 



Production in 1913 to 52,258 tons in 1917, while the produc- 



of the tion of plantation rubber during the same period 



World has increased from 28,518 tons to 204,251 tons. 



The present commercial rubber plantations are 



chiefly in the Malay Peninsula, which alone produces about one-third 



of all of the plantation rubber, and in the Dutch East Indies, Ceylon, 



India, Burma, and Borneo. The Far East now produces fully 80 per 



cent of the world's supply of crude rubber. It is believed that if the 



plantations in the Philippines were supported by capital as those of 



Malaya have been they would become an important factor in the future 



supply of rubber. In 191 3, 50,000 tons of rubber were imported into 



the United States, 30 per cent coming from the United Kingdom, being 



