1¾x3½-inch double-convex lens.
Reading-glass. Price $1.50; for $1.75 in new subscriptions. Postage 10 cents.
2⅞-inch lens.
Stereoscope on pillar. Price $1.25, for $1.50 in new subscriptions. Postage 25 cents.
1¾x3½-inch double-convex lens.
Reading-glass. Price $1.50; for $1.75 in new subscriptions. Postage 10 cents.
2⅞-inch lens.
Stereoscope on pillar. Price $1.25, for $1.50 in new subscriptions. Postage 25 cents.