Dipping Needle

Dipping Needle

Dip Needle

The dip needle is a black round cylinder with a glass top which reveals numbers ranging from 0 to 360 around the circumference of the cylinder. An arm extends from the side of the cylinder to the center and holds a magnetized needle. Needle swings on grid from 0 to 360 degrees. Two spirit levels, one circular and one tubular, aid in taking angle readings. Made by 'Sharpe Instruments Ltd. Toronto Canada' 'Ser 809'. Used by Dr. Aaro Aho in his mining exploration work.

The dip needle is a compass-like magnetic sensing instrument used by prospectors and geologists to measure the angle at which vein, fault or rock unit is inclined from the horizontal. The instrument is held vertically and the needle then points towards a strong magnetic field in the earth. It is essentially a magnetometer that was used for mapping mainly at high altitude. The dip needle is now obsolete, as it is not sensitive enough to detect all magnetic vectors, their strength, of the quality of the vein detected.

This dip needle belonged to Dr. Aaro Aho, a geological engineer and prospector who explored the Yukon, including the Keno Hill district for almost twenty seasons. He graduated from the University of British Columbia in 1949 with a B.A. and B.Sc. in geological engineering. After a working for the Geological Survey of Canada in northern British Columbia and Yukon, Dr. Aho went on to study at the University of California and later received a PhD from Oregon State University. His main field of study was in petrol, mineral deposits, geological structures and volcanoes. After earning his PhD in 1954, he was offered a position with the White Pass and Yukon Route. Dr. Aho returned to the north as an exploration manager for the company. Later he opened a consulting business and then Dynasty Explorations. While in the Keno region, he enjoyed collecting stories from the prospectors, old timers and the colourful townsfolk of the area. Before his accidental death in 1977, he wrote a manuscript about the prospecting, mining and settlement of Keno City and its environs. His book proved to be an instrumental log of historical events of that specific area of Yukon. His work in the mining industry in Yukon is legendary and so are his efforts for providing Keno City with a chronicle of the past.

Dr. Aaro Aho: Born of Finnish Canadian pioneer parents at Ladysmith, BC in 1925. He spent his youth on a farm on Vancouver Island. A love of applied science and outdoors led him to choose geological engineering as a profession, graduating with a B.A. and B.Sc. from University of British Columbia in 1949. After a stint with the Geological Survey of Canada in northern British Columbia and Yukon, Aho went on to study petrology, mineral deposits, geological structures and volcanology at the University of California at Berkeley. He gained a PhD in 1954, while teaching at Oregon State University. Offered a position with the White Pass and Yukon Route, he returned to the North as an exploration manager. Dr. Aho's field work led to a strong conviction that major mineral deposits were to be found which could open up Yukon in spite of its remoteness, lack of development, short seasons and severe climate. Dr. Aho began an independent consulting practice, exploring many areas, including the Keno Hill district, from 1959 to 1964. Finally, in 1964, after 10 years of optimism in the face of hard work, disappointments, and frustrations Dr. Aho formed Dynasty Explorations and headed the exploration team that discovered the large Anvil lead-zinc mine in central Yukon in 1965, worth several times that of the Klondike and Keno Hill combined, and involving over $100 million in new investment. He wrote the manuscript before his death in 1977 in a farming accident near Ladysmith, BC at the age of 51.


Keno City Mining Museum, Keno City

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