318 EARTHS PROPER. 



number nearly so high as 3 '375. Indeed, from 

 the constitution of alumina, there seems no rea- 

 son to doubt that %'%5 is the true atomic weight 

 of this earth. 



The probability is, that alumina is a protoxide 

 of aluminum. On that supposition, the atomic 

 weight of aluminum will be 1*25. 



SECT. II. 



OF THE ATOMIC WEIGHT OF GLUCINA. 



THOUGH glucina has been known to chemists for 

 more than twenty years, we are in possession of 

 very few experiments from which we can deduce 

 its atomic weight. Berzelius, so far as my know- 

 ledge extends, is the only person who has ana- 

 lyzed some of the salts of glucina with a view of 

 determining its capacity of saturation, from which 

 the atomic weight is easily deduced. Before re- 

 lating the experiments which I have made to 

 ascertain the atomic weight of this substance, it 

 will be interesting to state the experiments of 

 Berzelius, by which, in fact, my own were di- 

 rected. 



* Berzelius dissolved a quantity of glucina in 

 a by a n excess of sulphuric acid evaporated the 



13erzelius. * 



solution till the acid began to escape and then 

 washed it in alcohol to cret rid of the excess of 



