The monumental Dauprat Method is a book more hornists should be more familiar with today. While you can find it in French on ISMLP, it is available from Birdalone (in this photo depicted with the Farkas book, for comparison) in a spectacular English language edition. They describe it as follows:
The first complete English translation of this very influential method book by the most highly-esteemed Professor of Horn at the Paris Conservatoire in the nineteenth century is still available in a limited edition of 1000 numbered copies. Printed in its original size (10 1/4″ x 13 1/4″) on acid-free paper, with all musical examples, etudes, and a fold-out chart reproduced in facsimile. A new Introduction and Index have been written for this Edition, which is 500 pages long, in a specially designed, sturdy yet elegant binding of dark blue Japanese cloth.
As is obvious from the photo, it is a big book. A really big book (too big?), with not only text but also extensive exercises for high and low horn.
Have you played any Dauprat yet?
While the name does not seem very familiar today, actually we have all done exercises similar to those by Dauprat. Compare this exercise below, from the Méthode, pt. 2, p. 69, no. 12, to Kopprasch 10.
UPDATE: The following section was for many years in the Horn Articles Online website, and is based on materials published in the Historic Brass Society Journal 9 (1997).
Dauprat on the aesthetics of the natural horn.
One of the clearest discussions to be found on the tone of the natural horn was written by Louis-François Dauprat (1787-1868), who was professor of horn at the Paris Conservatory from 1816 until 1842. His monumental three-volume Méthode de Cor alto et Cor basse, published in 1824, contains a brief chapter titled “On the changes and improvements that some would like to see applied to the horn.” While his comments are not direct reactions to the valve, they are nevertheless enlightening
Some have wished that by means of holes and keys the considerable series of factitious sounds on the horn might be eliminated, while at the same time and in the same way those that are totally lacking in the low register would become possible. But this method, already applied to the [keyed] trumpet, has changed the timbre of the instrument to the point of giving it a quite peculiar character, creating an instrument which is neither a trumpet nor any other known instrument. …
The horn would probably fare likewise were it made to undergo similar alterations: it would lose its character and the true quality of its natural and factitious tones. Most of these latter have a charm that is particularly theirs, and which serve, so to speak, for shadings and nuances in contrast with the natural sounds. It must then be presumed that, far from gaining by their complete removal, the horn would lose a great deal. And what is said here about the various sounds of the complete range of the instrument must obviously extend to the different crooks. Each of these, taken by itself, has its own color, its timbre, and its special character; but if they were all combined in a single assembly, becoming but one and the same instrument, this instrument would certainly have, if you will, the same range of low, high, and middle sounds. However, the more the new inventions produce equality among all the sounds, the more the characters, colors, and timbres of the individual crooks would be distorted and confused.
While Dauprat in this article was primarily arguing against the keyed brasses, one gets the sense that he felt that valves were also a bad idea. He refers to two important underlying aesthetics of natural horn playing. The first is that the differences of tonal color resulting from the use of different crooks is to be desired artistically. The second and more critical is that the shades of tonal color resulting from performing melodies using hand horn technique were considered especially expressive nuances which should not be suppressed. They were a part of what made a horn sound like a horn and gave the instrument its special tonal color.
SOURCE
Louis-François Dauprat, Method for Cor Alto and Cor Basse (Bloomington: Birdalone Music, 1994), trans. ed. Viola Roth, part 1, 5 [13].
