Reginald Aldworth Daly
Overview
 
Reginald Aldworth Daly was a Canadian
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 geologist
Geologist
A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes and history that has shaped it. Geologists usually engage in studying geology. Geologists, studying more of an applied science than a theoretical one, must approach Geology using...

. He was a professor at Harvard University
Harvard University
Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...

 from 1912 until 1942, after working as a field geologist for the Canadian International Boundary Commission.

He examined the rocks along a 400 miles stretch at the 49th parallel
49th parallel north
The 49th parallel north is a circle of latitude that is 49 degrees north of the Earth's equatorial plane. It crosses Europe, Asia, the Pacific Ocean, North America, and the Atlantic Ocean....

, which led him to formulate a theory of the origins of igneous rocks, and published his seminal work Igneous Rocks and Their Origin in 1914.
 
x
OK