So, what was the motive? was it money?
According to the NY newspaper, the Sun, dated Tuesday, February 11, 1896, Max Eglau's watch and chain and other valuables were found undisturbed. He also had in his pockets three bank books which all showed considerable deposits. There was one book for the Metropolitan Savings Bank, another for the Bank for Savings and the third for the German Savings Bank.
Whether the $100. in bank notes which Mr Eglau was known to have had when he left home was stolen or if he actually deposited it on his way to the institution is a question which has yet to be answered. john B. Zink, Max Eglau's son-in-law, was the last family member to see him alive. Mr Zink said that his father-in-law had shown him $100. which he got by cashing his check for last month's work at Cooper union. He left at 11:00am en route to the German Savings Bank to deposit the money.
The following day, February 12, 1896, the newspaper, the Sun, stated that the statement of police Captain Casey that Eglau had no money is a direct contradiction of the statement made by his son-in-law. The professor's friends told the reporter that it was his habit to carry a large roll of bills with him which he displayed liberally. "If he bought anything, no matter how small, when he put his hand in his pocket to get the money he would always pull out a roll, and seemed to be proud of it. He was careless of it, too". About three weeks ago, Mr Eglau left an $80. roll in a closet at the institution. It was found by one of the inmates and he got it back. Mr Zink confirmed this story.
On February 14, 1896, the newspaper, New York Tribune stated that the money which Max Eglau had when he was murdered was found at the bottom of the dumbwaiter shaft in the "Deaf and Dumb Institute".
If money was not the motive, then what was?
Historic Newspapers at Library of Congress: