What does the number in parentheses mean in the Autograph Card listings?
This number indicates the total number of letters written and/or signed by the listed individual that are found in that collection. For example in collection 0160 the following listing is found in the Autograph Cards: Vance, Z[ebulon] B[aird] (3) 1890,1894. This means that three letters written and/or signed by Z. B. Vance in the years 1890 and 1894 are found in collection 160.