William Henry Howell
Appearance
![](http://upload.wikimedia.org/wikipedia/commons/thumb/1/12/William_Henry_Howell.jpg/250px-William_Henry_Howell.jpg)
William Henry Howell, Ph.D., M.D., LL.D., Sc.D. (February 20, 1860 – February 6, 1945) was an American-born physiologist best known for pioneering the use of heparin as an anticoagulant. He was born in Baltimore, Maryland.