John Philip Holland died on August 12, 1914 at the age of 74.
He invented the submarine, something like an underwater boat, if you don't know what it is.
The cause of his death in 1932 is unspecified. Since Sousa lived to be 77, he probably died of old age.
John Philip Sousa died of a heart failure on March 6th in 1932.
John Philip Holland was born on February 29, 1840.