Nor were Signal Corps achievements limited to the large vital assistance rendered to the Army itself, assuring the communications facilities that the commander must have in order to control his troops. The Signal Corps achievement in World War II must include, in any over-all estimate, mention also of its contribution to the civilian nation. Its co-operation and assistance boosted the relatively slight prewar electronics industry of the United States to a foremost place in the nation's economy after V-J Day. The Corps helped build new factories and uncover new supplies of raw materials, so many of which were rare, hard to discover, or refine in quantities, such as quartz crystals. It was large-scale quarrying of these, and the techniques of fabricating millions of frequency control crystals (where only very small quantities had been laboriously produced before the war) that made possible the simple push-button tuning of tens of thousands of vehicular and aircraft radios in World War II. The Signal Corps contributed thousands of new developments and inventions to the electronics technology of the era, adding greatly to the scientific skills and experience of the United States. And at the war's end it returned to civilian life and employment many tens of thousands of men and women whom it had trained in communications-electronics and who would apply their new and specialized knowledge to the immeasurable benefit of the nation's future progress.