[LB040188], Memorandum, West Orange Laboratory, New Jersey and Pennsylvania Concentrating Works, April 25th, 1890
https://edisondigital.rutgers.edu/document/LB040188
Transcription
April 25, 1890 New Jersey and Pennsylvania Concentrating Works Magnetic Dipping Compasses and Tripods. These instruments were made for the experts who are prospecting in New Jersey and Pennsylvania for iron ore. They are in the hands of these experts now and in daily use by them. Prospecting Instruments for Iron Ore. This was a delicate Dipping Needle for indicating the presence of iron ore furnished to one of the experts for prospecting in New Jersey and Pennsylvania. Respirator for Mr. Livor. This experiment was conducted at the request of Mr. Livor. The device was a mask covering the face for the purpose of preventing floating particles from entering the lungs.