:352 B. T. Patten: 



•tannin and kino. The difference between the un-treated specimen 

 and the oven-treated specimen is very small. Other experiments 

 gave the same results. Hence we may conclude that sudden drying 

 of the surface does not affect the ultimate rate of drying. 



The amount of shrinkage in breadth of these specimens is also 

 of interest : — . 



Treatment 



In Air 10 lbs. steam Steam at atmos. p. Oven at 110 

 Shrinkage - ^J - M " M - M^ 



These results are similar to those of other experiments. It will 

 be seen that the suddenly dried specimen gives the least shrinkage. 



The amount of shrinkage that takes place when our timber is 

 -seasoning, is highly important. The measurements taken are not 

 •extensive, but they should proves a guide for future w^ork. 



Measurements were raade on both Messmate and Mountain 

 Ash. In length the shrinkage is very small, and averaged 1/32 in. 

 for 6 ft. Lengths from 2 ft. to 6 ft. were used. 



For shrinkage in radial and tangential direction, 6 in. x 1 in. 

 boards were used mainly. The shrinkage in a tangential direction 

 is generally supposed to be much greater than in a radial direc- 

 tion, but the difference was not as great as expected. The results 

 ior Mountain Ash (E. regnans) are as follows: — 



In the radial direction the shrinkage averaged — 

 ^§in. for Gin. or about 5%. 



In the tangential direction the shrinkage averaged — 

 Jin. for 6in. or about 8%. 



For Messmate the results were as follows : — 



In the radial direction the shrinkage averaged — 

 yin for 6in. or about 6%. 



In the tangential direction the average was — 

 ^f for Gin. or about 8%. 



It is still a debated question as to how long it takes our timl)er 

 to season in the open air. Apparently no accurate observations 

 have been made, and hence doubt exists. In my former paper I 

 •gave some observations on the drying of a stack of timber. 

 Another stack was made in January of this year. The boards were 

 6 in. X 1 in., and were placed horizontally w^ith 1 in. fillets between 

 them. Laterally there was a 3 in. space between boards. There 

 Tvere 30 boards in the stack, each 6 ft. The stack was not in the 



