All the work of the Technologic Branch is being carried out along eminently practical lines, and is far removed from such work as can be taken up advantageously by private or by State agencies. The work of the Mine Accidents Division was taken up primarily to reduce the number of mine accidents, and to increase the general conditions of safety in mining. As the work of this Division has progressed, it has been found to be of great advantage to the miner and the mine owner, while the ultimate results of the studies will be of still greater value to every consumer of coal, as they will insure a continued supply of this valuable product, and at a lower cost than if the present methods, wasteful alike in lives and in coal, had been allowed to continue for another decade. A. BARTOCCINI, Assoc. M. Am. Soc. C. E. (by letter).--The writer made a personal investigation of the mine disaster of Cherry, Ill. He interviewed the men who escaped on the day of the accident, and also several of those who were rescued one week later. He also interrogated the superintendent and the engineer of the mine, and obtained all the information asked for and also the plans of the mine showing the progress of the work. After a careful investigation the writer found that the following conditions existed at the mine at the time of the disaster: _First._--There were no means for extinguishing fires in the mine. _Second._--There were no signal systems of any kind. Had the mine been provided with electric signals and telephones, like some of the most modern mines in the United States, the majority of the men could have been saved, by getting into communication with the outside and working in conjunction with the rescuers. _Third._--The miners had never received instructions of how to behave in case of fire. _Fourth._--The main entries and stables were lighted with open torches. _Fifth._--The organization of the mine was defective in some way, for at the time of the disaster orders came from every direction. _Sixth._--The air shaft was used also as a hoisting shaft. _Seventh._--The main shaft practically reached only to the second vein; its extension to the third and deepest vein was not used. _Eighth._--Plans of the workings of the second and third veins were not up to date. The last survey recorded on them was that of June, 1909. This would have made rescue work almost impossible to men not familiar with the mine. _Ninth._--The inside survey of the mine was not connected with the outside survey.