Despite this disruption, Cummings supervised the construction of several buildings, including Rich Library (now the Patricelli '92 Theatre), Memorial Chapel, and Orange Judd Hall.

He took up full-time preaching again in 1878 and continued to travel the country giving sermons until he was asked to become the President of Northwestern University in Evanston, Illinois in 1881.

[2][8] Cummings was able to increase faculty salaries, pay off Northwestern's debt, and add new buildings to the Evanston campus (e.g. Fayerweather Hall of Science in 1881, Dearborn Observatory in 1889, and Hatfield House, a dormitory for men, in 1890).

[2][9] During his lifetime, Cummings was widely recognized as a preeminent Methodist scholar and pastor, which is evident from the numerous honorary degrees he received for his good works.

[2] He was survived by his wife, Deborah, who remained a trustee of Northwestern University until her death in 1900, and his two adoptive daughters, Mary (born in 1846) and Alice (1856–1932).