[1][3][4] Gayley spent much of his early career working at various iron and steel companies throughout the northern United States.

He began his career working for the Crane Iron Company as a chemist, a position he held for three years with an annual salary of $500.

Gayley left this job to assume a management position at the E&G Brooke Iron Company in Birdsboro, where he worked for another three years.

One such invention incorporated charging bins which would mix, rather than heap, the various materials used in steel processing, allowing the ingredients to burn more evenly while using less fuel.

"[3] For leading these improvements, Gayley was given the post of General Superintendent to the entire Edger Thomson plant,[7] and by 1897 became the managing director of the Carnegie Steel Company.

[2][5] One of the most important of Gayley's inventions was his device which prevented water vapor in the air from entering the furnace - a process he called the "dry-air blast".

After its inception, this process was described as one of the "greatest achievements in modern metallurgical chemistry" by members of the Perkin Medal committee.

[3] Gayley was a member of both the American and the British Iron and Steel Institute,[3] and the Lafayette College Board of Trustees from 1892 until his death in 1920.

[12] Gayley made many contributions to the technical literature of metallurgy and other sciences, which were published three times per year in "transactions" by the American Institute of Mining Engineers.