Translations for roar in French

Here are paragraphs from public domain books translated:

A long, low moan, indescribably sad, swept over the moor. It filled the whole air, and yet it was impossible to say whence it came. From a dull murmur it swelled into a deep roar, and then sank back into a melancholy, throbbing murmur once again. Stapleton looked at me with a curious expression in his face.	Un long gémissement, indiciblement triste, courut mur la lande. Bien qu’il eût ébranlé l’air, il était impossible de préciser d’où il venait. Commencé sur une modulation sourde, semblable à un murmure, il se changea en un profond rugissement, pour finir en un nouveau murmure, mélancolique, poignant.
The Hound of the Baskervilles, by Arthur Conan Doyle	Le Chien des Baskerville, de Arthur Conan Doyle