This appeared in the June 16, 1876 issue of The Jewish Times; the author of this book wished to call attention to an error - a"blunder" as he put it - in his book, concerning the identity of the Rabbi Hillel mentioned in the Talmud who taught that there would be no future Messiah, as he had already come in the days of King Hezekiah. The author writes that he omitted the title "Rabbi" and so presented this Talmud figure as if he were Hillel the Elder.
Here's the footnote to which the author, Max Schlesinger, was referring. And I have to say - I am impressed that Schlesinger noted that he thought it was the 1st century Hillel, not the 3rd - he could have only said he omitted the honorific. Admitting this degree of error in so public a fashion is a breath of fresh air, fresh, 137-years old air.