Translations for frantic in French

Here are paragraphs from public domain books translated:

We were too astounded to speak. We could only stand there staring in amazement. A great broken bough upon the grass showed whence he had gained his leverage to tilt over our bridge. The face had vanished, but presently it was up again, more frantic than before.	Muets de stupeur, nous restions cloués sur place. Une branche cassée dans l’herbe, nous disait de quel levier il s’était servi pour faire glisser le pont. Sa face s’éclipsa un instant, puis reparut, plus frénétique.
The Lost World, by Arthur Conan Doyle	Le Monde perdu, de Arthur Conan Doyle