It was in 1816, after eight years of work on the problem, that her last memoir on vibrating surfaces was crowned in a public seance of the _Institut de France_. After this event Mlle. Germain was treated as an equal by the great mathematicians of France. She shared their labors and was invited to attend the sessions of the _Institut_, which was the highest honor that this famous body had ever conferred on a woman. The noted mathematician, M. Navier, was so impressed with the extraordinary powers of analysis evinced by one of Mlle. Germain's memoirs on vibrating surfaces that he did not hesitate to declare that "it is a work which few men are able to read and which only one woman was able to write." Biot, in the _Journal de Savants_, March, 1817, writes that Mlle. Germain is probably the one of her sex who has most deeply penetrated the science of mathematics, not excepting Mme. du Chatelet, _for here there was no Clairaut_.[125] Like Maria Gaetana Agnesi, Mlle. Germain was endowed with a profoundly philosophical mind as well as with a remarkable talent for mathematics. This is attested by her interesting work entitled _Considerations Generales sur l'Etat des Sciences et des Lettres aux Differentes Epoques de Leur Culture_. All things considered, she was probably the most profoundly intellectual woman that France has yet produced. And yet, strange as it may seem, when the state official came to make out the death certificate of this eminent associate and co-worker of the most illustrious members of the French Academy of Sciences he designated her as a _rentiere_--_annuitant_--not as a _mathematicienne_. Nor is this all. When the Eiffel tower was erected, in which the engineers were obliged to give special attention to the elasticity of the materials used, there were inscribed on this lofty structure the names of seventy-two savants. But one will not find in this list the name of that daughter of genius, whose researches contributed so much toward establishing the theory of the elasticity of metals,--Sophie Germain. Was she excluded from this list for the same reason that Agnesi was ineligible to membership in the French Academy--because she was a woman? It would seem so. If such, indeed, was the case, more is the shame for those who were responsible for such ingratitude toward one who had deserved so well of science, and who by her achievements had won an enviable place in the hall of fame.[126]