6 Relation between Forest Lands & Climate in Victoria. 



not diminish, it would become more fitful, and the country 

 more and more exposed to extremes of temperature, our 

 winds drier, and our soil more arid and sterile. For 

 conserving our allotted rainfall, tempering and moistening 

 the burning equatorial winds, for moderating the sun's 

 powerful rays, and the rapid terrestrial radiation, which 

 produces such low temperatures at night, and for checking 

 rapid evaporation, our forest lands are the chief agents. 

 Denude our timbered ranges, clear away our lower forests, 

 and our climate will soon become like those of some of 

 the similar latitudes in the northern hemisphere already 

 referred to, where no middle state is known between a 

 scorching arid summer and an intensely cold and equally 

 arid winter, tempered only by occasional heavy rains of 

 short duration. 



Moderate forest clearing in very humid climates is 

 doubtless beneficial, and many tropical regions have 

 been rendered habitable and healthy by the process ; but in 

 a dry climate like that of Southern Australia, the indis- 

 criminate clearing of timbered lands invites an ever- 

 increasing aridity of climate and diminishing fertility of 

 the soil. 



Art. II. — Experiments on the Tensile Strength of a few 

 of the Colonial Timbers. 



By Feed. A. Campbell, C.E. 



[Communicated May 8th, 1879.] 



These experiments were made at Geelong during a short 

 period of leisure time. As the power I could bring to bear 

 upon the specimens did not exceed a ton, I found it necessary 

 to work upon specimens with a sectional area of one- 

 sixteenth of an inch. The form of specimen first adopted 

 was that shown in figure 1, but as with the stronger woods 

 the specimens gave way by the detrusion of a piece from the 

 centre, as shown by dotted lines, I adopted a form, as in 

 figure 2, five inches longer. The apparatus used was of the 



