XXVIII.] 



DANTZIC FIR. 



237 



to bend or buckle up under the load, showing that 

 stiffness is an important element in the condition of 

 strength. 



Specimens were also tested measuring 4" X 4" (Table 

 CXXVIL), but the results obtained were scarcely so 

 satisfactory as before, in consequence of the sudden 

 falling off in strength in the 21 -inch piece; still there 

 is, perhaps, sufficient to indicate that the maximum of 

 strength would be in a length of about 20", in which 

 case the proportion of base to length would still be as 

 16 : 20 or 4 : 5. 



Table CXXVIII. shows the result of some vertical 

 tests on pieces 6" X 6" and even larger, but the lengths 

 are not in the same proportion to the scantlings 

 given in former tables, there not being any means at 

 my disposal for holding pieces of greater length than 

 30 inches. Whether the result would have been the ' 

 same if this had been possible, cannot therefore be 

 determined by the experiments herein referred to. 



TABLE CXXIL FIR (DANTZIC). 

 Transverse Experiments. 



' -\ Nos. i, 2, and 3 broke with a scarph-like fracture, io inches in length ; 4 and 5 a little 

 longer and more splintery : 6 about 15 inches, and also splintery. 



