In the early 1900's, were there typical sizes for glass negs? I have no idea what camera he used (I have a few of his later cameras), but my great-grandfather (I believe) took a picture of my grandmother as a baby sitting on someone's lap and the negative is 3 1/4" by 5 1/2". There are also other negs (different subjects and ages) that are smaller. The size just seems odd to me.