This excerpt is impossible on the natural horn, one could play less than half of the notes, which means that it is meaningless to give such a passage to the horn.
Why does it matter that Wagner heard Halévy’s opera and he liked the instrumentation? Because both Rienzi and Der Fliegende Holländer were premiered in Dresden, when he moved there in 1842, and of course, the ‘new parts’ required someone who could play them. Luckily, the orchestra in Dresden was at that time also one of the best in the world, therefore also the horn section was remarkable. The hornists of the Dresdner Staatskapelle in 1842: Carl Christian Eisner, Carl Gottlob Kretzschmar, Friedrich August Moschke, Johann Gottlieb Adam and Joseph Rudolph Lewy. The two specially notable people are Kretzschamer, who wrote the individual parts for Carl Maria von Weber, and Lewy. He and his brother are the most significant early valve horn players, with many pieces written for them and their new horn. J.R. Lewy was leading the horn section in these noticeable pioneer works, as the mentioned Wagner operas, or the Tannhäuser, but he and other members of the group worked together with Robert Schumann on his solo horn pieces.

 

The first orchestral piece which contains part for valve horn, is the La Juive by Jules Halévy. This piece presents perfectly how the instrument was used in Paris at the time. Since Joseph Meifred was one of the two players who played the cor á pistons part,1 there is no surprise that the parts have a lot of similarities to Meifreid’s treatise. The valve horn is not an individual instrument in the orchestra, the composer uses it more as a complementary instrument of the 3rd and 4th horn. The two valved instruments play in twenty-two numbers and only in seven on the piston horn, and mostly in the low register, and the stopped notes, like in the bar 9 and 13 in the example.

 

Richard Wagner, who was possibly the most inspiring composer for many other composers, was a quite rebellious person and musician as well. He tried to reform the orchestral sound, the art of opera writing; invented new instruments for his opera, for instance, Wagner-Tuba, bass trumpet, contrabass trombone. Thus it is not unpredictable that he was amazed by the orchestration and the use of the instruments in La Juive that he saw in Paris. As proof of his admiration, in Rienzi and in Der Fliegende Holländer, he already applied the new setup for the horn section. Of course, he acknowledged where he can best use the new instrument, and where he can give new character to the orchestration. This is how one of the first important excerpts for (low) valve horn was created.

 

The first appearance of the valve horn in the French, and afterwards in the German orchestral music

In Halévy’s opera, the main instrument is the natural horn, that is the reason why the second pair of horns has to change, not the first one; and why the natural horns have all the important moments, such as solos etc. As Meifred’s tutor shows too, the French saw that they can benefit the most in the mentioned places.2 We will see that it is different to the way the German composers  used the instrument. Wagner and Schumann put the Ventilhorns on the first place, not as complementary, but as fixed instruments, and the natural instruments formed the second duo. This means too, that the first horn, which has the most solos, has to perform on the valve horn, and the natural horns are responsible for the special sound colours and to draw the attention to the exceptional spots.