ALKALINE PHOSPHATES. 441 



Taking all these circumstances into consideration, and more- 

 over recollecting the importance of the earthy phosphates, and 

 especially of the animal substances containing phosphorus, we might 

 be disposed to believe the conclusion justified, which, it was 

 supposed, might be drawn from the abundance with which 

 alkaline phosphates occur in the ash. But, unfortunately, Rose's 

 improved analyses of the mineral constituents occurring in animal 

 bodies have deprived us of the basis on which this conclusion 

 rests. The earlier ash- analyses of the different animal juices can 

 no longer be regarded as affording evidence of the importance of 

 these alkaline phosphates : later and more perfect analyses, in 

 accordance with Rose's method, do not enable us to form a 

 decided opinion regarding the occurrence of preformed alkaline 

 phosphates in the different animal fluids, for it is not only the 

 alkaline phosphates contained in the aqueous extract of the carbo- 

 naceous residue of animal bodies which are to be regarded as pre- 

 formed in the animal body, but also those contained in the 

 hydrochloric extract, which were retained in the residue with phos- 

 phate of lime or of magnesia as insoluble double salts (Rose*). 



We cannot decide, in reference to these alkaline phosphates, 

 whether previously to their combining with lime or magnesia, they 

 existed preformed as basic alkaline phosphates, or rather, as Rose 

 thinks more probable, as alkaline carbonates or combinations of 

 alkalies with organic acids ; further, it has never been quite accu- 

 rately determined to what extent alkaline phosphates are produced 

 from phosphate of magnesia when decomposed by alkaline carbo- 

 nates. But putting out of view all these uncertainties, we should 

 not be too hasty in drawing conclusions from the results of such 

 analyses of the mineral constituents ; for the principle asserted by 

 Rose that the mineral bodies which cannot be extracted by hydro- 

 chloric acid from the carbonaceous residue of animal substances 

 must be regarded as non-oxidised, and as combinations of phos- 

 phuretted radicals with metals, is at present only an hypothesis, 

 although a very probable one. Such are the reasons which deter- 

 mine us for the present to suppress any consideration of the part 

 which the alkaline phosphates may take in the general metamor- 

 phosis of matter, or in individual animal processes. If however, 

 further investigations demonstrate, with greater certainty, the more 

 abundant occurrence of these phosphates in the individual animal 

 juices and in certain processes, our knowledge of the properties of 

 phosphate of soda, would readily lead us to understand in what 

 * Pogg. Ann. Bd. 77, S. 208-302. 



