For conservation purposes, the negatives were arranged and housed in boxes by format and by size. Glass slides are boxed separately from film. Within each format, 8x10, 5x7, and 4x5 size envelopes are boxed separately. Generally, the envelope size corresponds with the size of the negative, but some envelopes hold smaller negatives. Most notably, the small 35 mm strips are held in 8x10 sheets/envelopes.
Each negative (or 35 mm roll) has a unique control number, which is noted on the envelope housing the negative. Within each box, the negatives are arranged in control number order. This number was often written on the back of a related print thereby linking the print and negative. Accordingly, to facilitate finding a particular negative regardless of format or size, the container list is arranged in control number order. Each entry in the container list indicates a range of control numbers, the format and size of the negatives common to the range (which also indicates the size of the box they are in), and the box number in which the negative will be found.
There is not necessarily a negative for every control number in the ranges shown in the container list. Gaps are very common because of the designation of a control number to a negative other than one in the institutional archive, lost or destroyed negatives, or other reason. Because of the gaps, there is often a sharp discrepancy between the actual number of negatives and the number implied by the range. To correct for this, each entry in the container list includes a note concerning the subject matter of the negatives in the range with a parenthetical indicator of the approximate number of actual negatives, for example: "Exhibitions: Early American Toys (4)."
