Ways will be taught you to find the deviation yourself, and those ways are the only ones you can depend upon.
"Lectures in Navigation"
Ernest Gallaudet Draper
5. Anterior presentation; deviation of the head upward and backward.
"Special Report on Diseases of Cattle"
U.S. Department of Agriculture J.R. Mohler
4. Anterior presentation; downward deviation of head.
"Special Report on Diseases of Cattle"
U.S. Department of Agriculture J.R. Mohler