About this time, M. Mechain, who had been sent to Spain to prolong the meridional line as far as Formentera, died at Castellon de la Plana.  His son, Secretary at the Observatory, immediately gave in his resignation.  Poisson offered me the situation.  I declined his first proposal.  I did not wish to renounce the military career,—­the object of all my predilections, and in which, moreover, I was assured of the protection of Marshal Lannes,—­a friend of my father’s.  Nevertheless I accepted, on trial, the position offered me in the Observatory, after a visit which I made to M. de Laplace in company with M. Poisson, under the express condition that I could re-enter the Artillery if that should suit me.  It was from this cause that my name remained inscribed on the list of the pupils of the school.  I was only detached to the Observatory on a special service.

I entered this establishment, then, on the nomination of Poisson, my friend, and through the intervention of Laplace.  The latter loaded me with civilities.  I was happy and proud when I dined in the Rue de Tournon with the great geometer.  My mind and my heart were much disposed to admire all, to respect all, that was connected with him who had discovered the cause of the secular equation of the moon, had found in the movement of this planet the means of calculating the ellipticity of the earth, had traced to the laws of attraction the long inequalities of Jupiter and of Saturn, &c. &c.  But what was my disenchantment, when one day I heard Madame de Laplace, approaching her husband, say to him, “Will you entrust to me the key of the sugar?”

Some days afterwards, a second incident affected me still more vividly.  M. de Laplace’s son was preparing for the examinations of the Polytechnic School.  He came sometimes to see me at the Observatory.  In one of his visits I explained to him the method of continued fractions, by help of which Lagrange obtains the roots of numerical equations.  The young man spoke of it to his father with admiration.  I shall never forget the rage which followed the words of Emile de Laplace, and the severity of the reproaches which were addressed to me, for having patronized a mode of proceeding which may be very long in theory, but which evidently can in no way be found fault with on the score of its elegance and precision.  Never had a jealous prejudice shown itself more openly, or under a more bitter form.  “Ah!” said I to myself, “how true was the inspiration of the ancients when they attributed weaknesses to him who nevertheless made Olympus tremble by a frown!”

Here I should mention, in order of time, a circumstance which might have produced the most fatal consequences for me.  The fact was this:—­

I have described above, the scene which caused the expulsion of Brissot’s son from the Polytechnic School.  I had entirely lost sight of him for several months, when he came to pay me a visit at the Observatory, and placed me in the most delicate, the most terrible, position that an honest man ever found himself in.