NOVEMBEP 1, 1907] 



SCIENCE 



573 



solutions, on being diluted with water, 

 throw down precipitates of a highly basic 

 nature, or on evaporation leave gummy 

 masses, the basicity of which depends upon 

 the amount of the dissolved hydroxide, 

 while, physically, they differ but little. 

 Both the precipitated bodies and the resi- 

 dues of evaporation are amorphous and 

 glassy in structure and vary widely in com- 

 position. The basic precipitates on equi- 

 librium, being reached, approach closely 

 to the hydroxide in composition, but always 

 contain a small amount of occluded acid 

 or normal salt, which it is impossible to 

 entirely remove by washing. These facts 

 have given rise in literature to a large num- 

 ber of so-called basic compounds which 

 have no existence as independent individ- 

 uals, but are in reality the impure hydrox- 

 ide, or, perhaps, more properly come under 

 the domain of homogeneous phases of vari- 

 able composition or solid solutions. 



It is, indeed, difficult to understand how 

 the solution of the normal sulphate, nitrate 

 and chloride can dissolve several equiva- 

 lents of their own hydroxide, attack metals 

 and carbonates almost as vigorously as if 

 they were the free acids themselves yield- 

 ing these basic solutions, and still be less 

 hydrolized than the corresponding salts of 

 aluminum and iron as Leys and Brunner 

 have both shown to be the case. It is, per- 

 haps, equally difficult to demonstrate why 

 the basic solutions so obtained should have 

 less osmotic activity per equivalent of the 

 acid present than the normal salts, should 

 show no indication of a colloidal nature 

 and should contain no complex anion, but 

 this is, indeed, the fact. The most prob- 

 able explanation would seem to be that we 

 have here a case of simple solution of a 

 substance (beryllium hydroxide) in a 

 mixed solvent (water and normal salt) in 

 one of which alone (water) it is insoluble. 

 The whole action of these solutions is per- 

 fectly analogous to those cases where a 



substance, being dissolved in a mixed sol- 

 vent, raises the freezing point whenever it 

 is insoluble in that component which sepa- 

 rates as the solid phase on cooling and 

 which Miller has mathematically shown is a 

 necessary sequence of the theorem of 

 Gibbs. 



In contradistinction to the basic solu- 

 tions, solid or liquid, already mentioned, 

 we have the truly phenomenal and actually 

 basic compounds of beiyllium, discovered 

 in Urbain's laboratory by Lacombe, which 

 are produced pure only in contact with 

 anhydrous acid or acid so nearly anhydrous 

 that the mass of the water present becomes 

 negligible to produce hydrolysis. These 

 very interesting, volatile and perfectly 

 unique basic compounds are apparently 

 confined to the fatty acid series and have 

 the general formula Be40(AC)a. Of these 

 the formate, acetate, propionate, butyrate, 

 isobutyrate and isovalerianate have been 

 made and studied. 



And now after this brief summary of 

 the main characteristics of the chief classes 

 of beryllium compounds I must, in closing, 

 honor those who have been most prominent 

 in developing our kaowledge of this ele- 

 ment by mentioning the names of Vau- 

 quelin, Wohler, Bussy, Andejew, Weeren, 

 Debray, Joy, Gibbs, Atterberg, Nilson and 

 Pettersson, Humpidge, Hartly, Kriiss and 

 Moraht, Lebeau, Rosenheim and Itsig, and 

 Urbain and Lacombe and paying my sIh- 

 eere respect to the many others who, from 

 time to- time, have struggled through the 

 difficulties incident to the peculiar and de- 

 cidedly vagarious action of this element to 

 greater light and truth. And finally I feel 

 that I should call the attention of this 

 inorganic section most particularly to the 

 fact that not only the future chemistry of 

 beryllium, but of all the elements in our 

 branch of the greatest of sciences, is be- 

 coming more and more dependent for its 

 exactness and wealth of discovery upon the 



