Two kinds of dynamite

I'm recently back from the Objectivist Summer Conference in Telluride, Colorado. During the outing to the nearby town of Ouray, set in a valley on on which Ayn Rand based the fictional Galt's Gulch, I took shelter from the rain in the local museum. Here, among the collections of rusty nails, old bottles and photographs of local worthies, I found this box:

The Atlas Powder Company, it seems, supplied high explosives. But for a real blast, only this Atlas will do:

This is the old Signet edition - the one I read back in the early 1970s (though not that particular copy, which disintegrated long ago). Apart from the sentimental value, it's much more attractive than the latest Penguin edition with the hideous Tamara de Lempicka painting on the cover.