Not that I find it better than modern tackle, there's is (for me at least) a joy in fishing a 4-wt splitcane rod with a silk line and an old Hardy reel, just occasionally, because there's really no question that modern tackle out-performs this old stuff by miles. But there's a tangible connection to the origins of this hobby/life style, just by discovering what the tackle they used felt like. I still haven't gotten around to horse hair casts yet, but I will at some point.
"A cast" is just an old expression for what we now call a leader and in the old days they were made of either horse hair or silk gut. This was the standard up until after World War II, where the production of nylon really began. From here on, nylon began to seriously take over for horse hair and gut, but horse hair was still in more or less common use up into 1960ies, maybe even 1970ies in some areas.
Both horse hair and gut abviously performed well (they caught fish after all), but in relation to nylon had one main difference. It had to be kept moist. For this purpose leader boxes were used. They were equipped with a piece of fleece or thin leather that one would moist to keep the casts moist and ready fro use. They also had the benefitof being able to store a two- or three fly cast rigged and ready-to-go with minimal tangle.
Today many use a rectangular piece of foam with slits cut in two sides to hold an extra leader. I for instance always carry a few leaders with droppers (no flies attached) when fishing the salt, because I want to be able to switch to a two-fly-leader quickly with the hassle of having to tie one, potentially with cold, wet hands.
But I don't often use the foam-things. They are of course practical: extremely light weight, impervious to saltwater an easily customisable. But I dislike having to straighten out the sharp kinks they sometimes make in the leader. So I of course use a leader box from "the old days".
Made from aluminium, it handles saltwater well, but of course the felt pad I just leave in there to protect the leaders a little bit (although there are no sharp edges). They're not hard to come by and rarely cost much, and I really enjoy using them. There are many alternatives, though. Zip lock bags, empty leader material spools, some even make foam spools for the same purpose that avoidds the kinks and there are also dedicated, small leader files.
But I of course like to use this old things, because I find them really practical and as with a split cane rod and a silk line, there's a nice continuum of old traditions. And as I think primarily the Americans say: "Why fix it if it ain't broke?"
Have a great weekend!
PoD: To the left, one of the ones I use and to the right a recent acquisition. As you can see, sometimes when you get hold of old ones, they contain old leaders, or "casts".