さく岩抵抗に関する研究 (第1報)

抄録

It is a fact that rock drillng is a highly important operation occupying practiclly all the space in the field of mining but it is far from satisfaction and one cannot stop thinking that the systematic study on this is in a childish stage as there are still some problems left in the study on the physical analysis of rocks.
In the following papers, the writer has. first of all, defined the hardness of rocks using the apparatus devised by himself which is the first of its kind and has adopted the said hardness as a scale to show the degree of resistance in rock drilling. The writer has then made a careful stgdy into the relation between the hardness defined by hims elf and that obtained in actual operation as well as the relation with the various natures of rocks and finally, he hasdiscovered that the observation, taking into account of the void, will bring about a still more favourable result.