This public domain dog image is a sketch of a pointer. While the breed is never mentioned, it would appear that this drawing depicts one of the hunting dog species which points in the direction of the scent it has found.
Whether you specifically need a drawing of a pointer or are just looking for a dog sketch or dog image, this little drawing just might be what you are looking for.
Thomas E. Hill must have spent years writing his book Hill’s Album of Biography and Art. It was published in 1882 with hundreds of wonderful illustrations and what appear to be stock print foundry images. Over 200 of them can be found here on Reusable Art.
This image is copyright free and in the public domain anywhere that extends copyrights 70 years after death or at least 120 years after publication when the original illustrator is unknown.