XX Trans. Acad. Sci. of St. Louis. 



Meeting of January 20, 1902. 



President Eliot in the chair, nineteen persons present. 



Dr. George Richter addressed the Academy on the physi- 

 cal and chemical properties of gelatin, which he described as 

 a spongy substance differing materially from other solids. 

 The manner of manufacture of gelatin and its chemical and 

 physical characters were described in detail, and considerable 

 attention was given to the rate of absorption and evaporation 

 of water by gelatin and the phenomenon of its apparent 

 solution in water. A new hygrometer was exhibited and 

 described, tlie action of which was based upon the water 

 absorption of gelatin. 



One person was proposed for active membership. 



Meeting of February 3, 1902. 



President EUot in the chair, nineteen persons present. 



Mr. Trelease presented, with the aid of lantern illustrations, 

 some of the principal results of his recent studies of Yuccas 

 and their allies. 



One person was proposed for active membership. 



Meeting of February 17, 1902. 



President Eliot in the chair, twenty -nine persons present. 



Dr. Gellert Alleman addressed the Academy on the chem- 

 ical constitution and the manufacture of Portland cements. 

 The growth of the cement industry was treated, the various 

 steps of development being shown by lantern slides illustrating 

 past and present types of machinery employed in its manu- 

 facture. Several slides were shown giving tabulated results 

 of a number of analyses of different commercial Portland 

 cements. 



Mr. Charles Espenschied read a letter from Mr. Seymour 

 Carter, of Hastings, Minnesota, in which was described a 

 method of Professor Anderson of Columbia University, New 



