 Comstock studied law in Bangor, Maine, and later, in 1868 and 1869, continued his studies at the University of Michigan at Ann Arbor.He moved to Nebraska in 1869 and settled in Omaha, where he was admitted to the bar the same year and commenced practice.He moved to Minneapolis, Minnesota in 1870 and to Moorhead, Minnesota in 1871, where he continued the practice of his profession; prosecuting attorney for Clay County 1872 – 1878.