VOL. LXXII.] PHILOSOPHICAL TRANSACTIONS. 177 



distillation, the fluid collected in the receiver was found to be vinegar. 



Exf}. 120. Sal Mirabile Glauberi. The acid of fat and this salt were mixed 

 together in equal weights, and were afterwards subjected to distillation. The 

 fluid collected in the receiver, in addition to the smell of the acid of fat, had 

 something of a sulphureous smell mixed with it. On adding some of this 

 distilled fluid to a solution of lead in acid fat, a white precipitate was thrown 

 down; a proof that a small quantity of the vitriolic acid had been disengaged 

 from the alkali with which it was before united. This Dr. C. attributes to the 

 phlogiston still adhering to the acid of fat, by which phlogiston (according to 

 his explanation) a portion of the vitriolic acid is rendered more volatile. 



Exp. 121. Tartarus tartarisalus. The acid of fat being added to a solution 

 of this salt in water, a copious precipitation took place. On pouring off the 

 liquor, the sediment had the taste and other properties of cream of tartar. 



Dr. C. concludes with some remarks on the relationship or affinity between the 

 acid of fat and the muriatic acid. Both acids yield a dry ammoniacal salt with 

 the volatile alkali, and with magnesia alba a deliquescent salt. Both precipitate 

 silver and mercury from their solutions in other acids; and when water is added 

 to a solution of regulus of antimony in either of these acids, a precipitation 

 takes place. And further, when muriatic acid is added to a solution of silver or 

 mercury in the acid of fat, nothing is precipitated. But there is a remarkable 

 difference between them in other respects. For instance, the acid of fat com- 

 bines intimately with oily substances; the salt which it forms with calcareous 

 earth is not deliquescent; ether is easily prepared from it; and it throws down a 

 precipitate from a solution of corrosive sublimate. 



///. Observations on the Bills of Mortality at York. By William White, M. D., 



F. A. S. p. 35. 



Mr. Drake, p. r. s., in his Antiquities of York, has given the number of 

 births and burials for 7 years; from Aug. 5, 1728, to Aug. 5, 1735, 

 inclusive. This gave a favourable opportunity of comparing our present state 

 after an elapse of 45 years. In order to this, the different parish registers were 

 carefully examined from Jan. 1, 1770, to Dec. 31, 1776, inclusive. 



Table 1 shows the number of births and burials in York from Aug. 5, 1728, 

 to Aug. 5, 1735, for all the several parishes, which collected together are, 2803 

 births, and burials 3488. The burials therefore exceeded the births by 685 in 

 7 years, or 98 annually. 



Table 2 shows the number of births and burials from Jan. 1, 1770, to Dec. 

 31, I776, inclusive: and these are, in like manner, 3323 births, and 3175 

 burials. Therefore decreased in burials 313, or 44f annually; births increased 

 520, or 743- ditto; births exceed the burials 148, or 21 4- ditto. 



The 3d table shows the number of births and burials, with the proportion of 

 males and females, annually, from Jan. 1, 1770, to Dec. 3 J, 1776. The 

 result of all is as follows : 



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