1870s CC Shepherd Slant Slate with Eight Double Sided Insert GuidesI've always wanted to find one of these, but this is the first I've come across still with its full deck of inserts, and an early one made by CC Shepherd c. 1875. There were two different versions of this produced: one opening like a desk to store the guides (and chalk) inside, and this one, with a niche at top into which the plates fit together stacked. (There is an orange ribbon visible when they are removed, the end of which would have served as a