The books I'm referring to can be downloaded at the On-Line Digital Archive of Documents on Weaving and Related Topics website under the book section. The specific books I am referring to were by Thérèse de Dillmont.
Unfortunately, some books have to be downloaded in parts, so I cannot always just provide one convenient link. This is not the complete list of DMC books available; these are the books that looked most appealing to me. Feel free to do your own exploring.
(Update Jun 2019: Sadly, it looks like the original resource no longer is available. I did find some of the catalogs available at the Antique Pattern Library here.)
Dillmont, Thérèse de. Alphabet de la Brodeuse [The Embroiderer's Alphabet], Dillmont, July 1932, 151 pages. Pretty much what you would guess; lots of options for alphabets.
here. Some wonderfully appropriate patterns.
here. Another great set of patterns.
Dillmont, Thérèse de. Le Filet Brodé [Embroidered Filet], Bibliotheque DMC, August 1912, 60 pages. Download here. Filet lace is very period, but I know my limitations and won't ever make my own curtains.
Dillmont, Thérèse de. Motivi per Ricami (3a Serie )[Embroidery Motifs], Bibliotheque DMC, 29 pages. Download here. Some lovely delicate embroidery patterns.
Dillmont, Thérèse de. Motivi per Ricami (Serie IV)[Embroidery Motifs], Bibliotheque DMC, 29 pages. Download here. More pretty flower borders. These would be so nice on small table scarves.
Finding great pattern books like this make me a little sad I don't spend more time doing handcrafts. Pre-internet, I would do cross stitch and embroidery. Nowadays, I almost always have a computer in my hands if I'm sitting on the couch.