He contributed over ninety article to the American Mathematical Monthly and wrote many biographies of mathematicians such as Lambert, Farkas Bolyai, Lobachevsky, De Morgan, Sylvester, Chebyshev, Cayley, Hoüel and Klein .
Siya ambag sa siyamnapung article sa Amerikanong matematiko at Buwanang wrote maraming mga biographies ng mga mathematicians tulad ng Lambert, Farkas Bolyai, Lobachevsky, Mula Morgan, Sylvester, Chebyshev, Cayley, Hoüel at Klein.