In 1974, Art Fry, a 3M chemical engineer, was attending Sunday morning church in his hometown.Fry was in the habit of marking his favorite church hymns by putting pieces of paper between the pages like a bookmark. But these tiny pieces of scrap paper would fall out of the hymnal. Then Fry came across the research of another 3M scientist, Dr.Spencer Silver. Silver had started experimenting in 1968 with an adhesive for general industrial purposes. The adhesive could stick to surfaces like glue, but did not leave any leftover residue.