304 Prof. Berzelius on [April, 



We find, therefore, the same relation between the protoxide 

 of iron and the barytes, as in the salt with base of potash ; on 

 the other hand, the relation of the water to the bases exhibits, in 

 this instance a remarkable exception to the ordinary rule, an 

 exception that might very well be attributed to inaccuracy of 

 observation^ if the loss which this salt experiences by efflores- 

 cence were not so uniform and so easy to be correctly deter- 

 mined. When we compare the relation of the capacity of 

 saturation of the bases, to the quantity of the substance lost in 

 the analysis, with that observed in the salt with base of potash, 

 "we find, in the salt with base of barytes that the loss exceeds 

 that in the salt with base of potash by a quantity precisely equal 

 to that which the water wants (que I'eau a doiuie en moins) to 

 make its oxygen twice * that of the barytes, and six times that 

 of the protoxide of iron. We shall soon see that this water is 

 found again, when this salt is burned by means of oxide of 

 copper. 



(C.) Salt with Base of Lime, 



This salt was prepared nearly in the same manner as the 

 barytic salt. It is very soluble in water, and does not crystallize 

 till the solution has acquired a syrupy consistence, and after 

 some days rest. The crystals are usually large, and of a pale 

 yellow colour. 



One hundred parts of this salt, exposed to the heat of a sand- 

 bath, lose 36-61 per cent, of their weight of water of crystalliza- 

 tion. The crystals, notwithstanding this large quantity of water, 

 do not fall to powder, and I have observed that although this 

 salt begins to effloresce as readily as the preceding, a higher 

 temperature is requisite to deprive it of the last portions of 

 water. The anhydrous salt, burnt like the preceding in an open 

 vessel, gave 50*53 per cent, of its weight of a mixture of oxide 

 of iron, caustic lime, and carbonate of Hme. It was dissolved 

 in muriatic acid, perfectly neutralized by caustic ammonia, and 

 precipitated by succinate of ammonia. The succinate of iron, 

 burned on an open capsule of porcelain, left 15*25 parts of oxide 

 of iron. The solution, from which the iron had been separated, 

 gave, by precipitation by oxalate of ammonia, oxalate of hme, 

 which, bemg decomposed by heat, left 39*21 parts of carbonate 

 of lime. This carbonate, moistened with a solution of carbon- 

 ate of ammonia, and then thoroughly dried, gained nothing in 

 weight. The analysis, therefore, gave 



Oxygen. 



lime 22*45 containing 6*20 .... 2 



Proxide of iron. . . 13*69 3*12 .... 1 



Water 39*61 ; 35*21 .... II4- 



Loss 23*85 



* Query, three time»r 



