The collection contains 479 dry gelatin glass plate negatives measuring 5 x 7 inches that document the construction of Lake Carnegie in Princeton, NJ. There are also 314 black and white paper prints developed approximately at the time the photographs were taken. The negatives and prints date from circa 1905 to 1907, with the bulk dating from 1905 to 1906. In addition, there are 38 amateur prints taken in March through May 1905 depicting the land before any construction work commenced, and two photograph albums containing construction images.

It is not known who took the photographs that document the construction of Lake Carnegie, but there are several possibilities, and because there appears to be more than one negative numbering system there may have been more than one photographer. The engineer of the lake project would have overseen the taking of photographs, and upon the death of J. J. R. Croes a great deal of photographic equipment and supplies were inventoried in his office. However, it is unlikely that Croes took the photographs himself; as engineer of the entire Lake Carnegie project he would probably have hired a photographer. F. P. Gridley, who worked as foreman and timekeeper of the lake project, owned copyright of the photographic souvenir booklet published for the lake's opening celebrations (1906), but Gridley is never mentioned in the records of the lake project as the photographer. James M. McKenzie writes to Alexander Gulick that he was making a complete photographic record of the work done on the lake, but because McKenzie also writes to Gulick of "the photographer" or "his photographer" at various points, it does not seem likely that McKenzie took these photographs. At the end of December 1906 McKenzie wrote to Gulick that a photographer by the name of Hazard was going to come to take photographs of the lake. This must refer to E. W. Hazard, and there is one photograph taken by E. W. Hazard of the Delaware & Raritan Canal in the Historical Photograph Collection - Grounds and Buildings Series - Lake Carnegie. Hazard may have taken some of the construction photographs, although he did not sign any of the negatives or prints found in the negative boxes as he did the photograph of the Canal.

As mentioned above, there appears to be more than one system of numbering the Lake Carnegie glass plate negatives. In some instances there are duplicate negative numbers, and some negatives have what appears to be a date indicated on the negatives. For example, a negative in the box identified as "Washington Street July" is labeled "864 7/3." This may indicate that the photograph was taken on July 3, but this is not certain and should not be taken at face value.