Description: |
"The nature of my invention consists in certain devices whereby two vises are so arranged as to revolve about a common center, and which many be locked firmly in any determined position... and which I call a 'compound revolving vise.' The particular use to which I have applied my invention is to hold gas pipe fittings for the purpose of tapping, screwing and boring them."According to the 1873 "Subject-matter index of patents for inventions issued by the United States Patent Office", this patent was granted an extension. |
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