226 Royal Academy of Sciences of Paris. 



four classes of vertebrated animals, before and afterbirth, and 

 at different ages ; a gold medal of the value of 3000 francs. 

 2. Mathematical prize for 1827 ; for a method of calculating the 

 perturbations of the elliptical motion of comets, applied to the 

 determination of the next return of the comet of 1759, and to 

 the motion of that observed in 1 805, 1819, and 1 822, — the same 

 reward. 3. Mathematical prize proposed in 1822 and re- 

 vised for 1827; first, for determining by multiplied experi- 

 ments the density acquired by liquids, especially mercury, 

 water, alcohol and sulphuric ether, by degrees of compression 

 equal to the weight of many atmospheres ; and secondly, for 

 measuring the effects of the heat produced by such compres- 

 sion, the same reward. 4. Prize founded by M. Alhumbert : As 

 no satisfactory memoirs had been received for this prize, the 

 Academy determined that the sums destined for the prize 

 should be united with those which will be due hereafter, to 

 form a prize of 1200 francs, to be awarded, in 1829, to the 

 best memoir on the following subject : A complete explanation, 

 accompanied with figures, of the changes undergone by the 

 skeletons and the muscles of frogs and salamanders at the 

 different epochs of their life. 5. Montyon prize in Experi- 

 mental Physiology: in 1827 the Academy will adjudge a gold 

 medal of 895 fr. value, to the printed or manuscript work 

 communicated to them before the 1st of January 1827, which 

 shall appear to have contributed in the highest degree to the 

 progress of experimental physiology. 6. Montyon prize in 

 Mechanics : in 1827 the Academy will award a prize of 1000 

 fr. to the inventor or improver of instruments useful to the 

 progress of agriculture, the mechanical arts, or the sciences. 

 7. Grand prizes from the Montyon legacy for the Improve- 

 ment of Medicine and Surgery, and also for the Means of 

 lessening the Unwholesomeness of any Art or Trade. The sums 

 which will be awarded to the successful authors of discoveries 

 or works on these subjects cannot be indicated prospectively, 

 but they will greatly surpass the value of the highest prizes 

 hitherto bestowed ; so that the authors will be reimbursed for 

 the expensive experiments or researches which they may un- 

 dertake, and will receive recompenses proportioned to the 

 services they may render, whether in preventing or greatly 

 diminishing the unwholesomeness of certain professions, or in 

 improving the medical sciences. The memoirs and instru- 

 ments must be transmitted to the secretary before February 1, 

 1827 ; and the prizes will be adjudged in the public sitting of 

 the same year. 8. The Delalande prize in Astronomy, con- 

 sisting of a gold medal 625 fr. in value, will be awarded in 

 1827. 9. Prize in Statistics: the Academy not having found 



occasion 



