758 



REPORT — 1897. 



jrreatest fibre stress by adding the direct stress per square incli to tlie greatest 

 fibre stress arising from the bending moment due to the eccentricity of the load ; 

 and we ehould then so proportion the column that the total greatest fibre stress 

 shall not exceed a certain allowable fibre stress, which last must be a sufficiently 

 small fraction of the breaking strength per square inch corresponding to the ratio 

 of length to radius of gyration of the column, as shown by the diagrams. 



In the paper itself the results of the tests and the modes of computation, both 

 for central and for eccentric loads, were treated more in detail, and then a discus- 



FlG. 3.— Diagrams of Results of Tests of Timber Columns. 

 YELLOW F/NE. 



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sion was given of the theories and formulfe commonly found in the handbooks 

 which are, for the most part, based on the results of Ilodgkinson'a tests on small 

 samples, and fuller attention was also called, in the paper, to the disagreement of 

 these latter with the facts. 



3. Results of Experiments on the Strength of White Pine, Red Pine, 

 Hemlock, and Spruce. By Professor H. T. Bovey, M.Inst.C.E. 



This Paper contained 10 Tables giving the results of experiments on the trans- 

 Terse strength of 29 beams: of these, nine were of white pine, eight of red pine, 

 seven of hemlock and fve of spruce ; while nine were kiln-dried, four were 

 saturated and frozen, and sixteen were more or less air-dried. 



The Paper also contained seventeen tables giving the results of experiments on 

 the direct tensile and compressive strength and of the shearing strength of speci- 



