This collection is a folio of reproductions from the Eberhard Faber Co. of pencil sketches done with Van Dyke pencils. This particular set seems have been prepared for Spanish-speaking markets, and consists of about 15 sketches and a few advertisements on A4 paper, all in an outer wrap whose texture is similar to construction paper.
The paper that the sketches are printed on is rather thick and smooth, but is starting to show the first signs of discoloration. But for being 90 years old they are in excellent condition.
During the early 1920s, Eberhard Faber held a contest for readers to submit sketches made with Van Dyke pencils. It seems many of the sketches in this folio were entries or even prize winners of this contest. For example, here is one of the sketches having won first prize, announced a 1922 issue of Architectural Digest:
I’m not certain if this is a complete set or if there were several sets issued at the time; I have seen several sketches in this format as advertisements but were not on this set. But they all seem to be part of a large push by the Eberhard Faber Co. for their Van Dyke drawing pencil, which at the time was their premium line.