An interesting note about John Root & Son's appears in a Goverment publication from 1893 U. S. DEPARTMENT OF AGRICULTURE.: DIVISION OF CHEMISTRY BULLETIN No. 13 WASHINGTON: GOVERNMENT PRINTING OFFICE 1893 John Root & Son, Mechanicstown, Md. Two samples of "Pen-Mar" corn (Nos. 10751 and 10915) were examined. No. 10915 contained sulphurous acid, but salicylic acid, copper, and zinc were absent from both.
