h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I've been a french horn player for 6 years, and although I am no more than a mere stripling of a horn player, I have never in my life heard of a triple horn. No where is it mentioned in musical dictionaries, not in encyclopedias and not on the internet. My tutor has mentioned nothing to me. Could you please tell me about the triple french horn because I'm dying to know the third horn that is combined into the instrument. I know that the double horn is the Bb and F, I play one myself. But what is the triple???

The triple horn can be one of a lot of things. As you may have worked out it involves a third set of valves, and it can essentially be anything, but in general, the most common triple horn has an F side, a Bb side and an F alto side. Another common variant has an F side, a Bb side and an E side (for handstopping) I hope this answers your question.