Answer by taking a quote from the following article:

Matthew Fontaine Maury (January 14, 1806 - February 1, 1873) was an American astronomer, United States Navy officer, historian, oceanographer, meteorologist, cartographer, author, geologist, and educator. He was nicknamed "Pathfinder of the Seas" and "Father of Modern Oceanography and Naval Meteorology" and later, "Scientist of the Seas" for his extensive works in his books, especially The Physical Geography of the Sea (1855), the first such extensive and comprehensive book on oceanography to be published. Maury made many important new contributions to charting winds and ocean currents, including ocean lanes for passing ships at sea.

The war brought ruin to many in Fredericksburg, where Maury's immediate family lived. Thus, returning there was not immediately considered. After the war, after serving Maximilian in Mexico as "Imperial Commissioner of Immigration" and building Carlotta and New Virginia Colony for displaced Confederates and immigrants from other lands, Maury accepted a teaching position at the Virginia Military Institute, holding the chair of physics.  Maury advocated the creation of an agricultural college to complement the institute. That led to the establishment of the Virginia Agricultural and Mechanical College (Virginia Tech) in Blacksburg, Virginia, in 1872. Maury declined the offer to become its first president partly because of his age. He had previously been suggested as president of the College of William & Mary in Williamsburg, Virginia, in 1848 by Benjamin Blake Minor in his publication the Southern Literary Messenger. Maury considered becoming president of St. John's College in Annapolis Maryland, the University of Alabama, and the University of Tennessee. It appears that he preferred being close to General Robert E. Lee in Lexington from statements that Maury made in letters. Maury served as a pall bearer for Lee.  During his time at Virginia Military Institute, Maury wrote a book, entitled The Physical Geography of Virginia. He had once been a gold mining superintendent outside Fredericksburg and had studied geology intensely during that time and so was well equipped to write such a book. During the Civil War, more battles took place in Virginia than in any other state (Tennessee was second), and Maury's aim was to assist wartorn Virginia in discovering and extracting minerals, improving farming and whatever else could assist it to rebuild after such a massive destruction.  Maury later gave talks in Europe about co-operation on a weather bureau for land, just as he had charted the winds and predicted storms at sea many years before. He gave the speeches until his last days, when he collapsed giving a speech. He went home after he recovered and told Ann Hull Herndon-Maury, his wife, "I have come home to die."

How often did this take place?
He gave the speeches until his last days, when he collapsed giving a speech.