VOL. XV.] PHILOSOPHICAL TRANSACTIONS. 127 



turn signifies nothing, for even that may be easily parted. 5. All acida are 

 volatile, because they yield a strong scent, which comes from their volatile salt. 

 Now since we can find no inflammable acid in the world, we may properly infer 

 spirit of wine to be no acid, because it takes fire and burns. He concludes with 

 a definition of acidum. Quod acidum sit sal fluore potitum, vim habens astrin- 

 gendi et coagulandi. 



M. Kunkel, in his answer, grants the first position. To the second he 

 gives a check, blaming his not distinguishihg between the acida regni mineralis 

 et vegetabilis. The next position he denies absolutely. To the 4th position he 

 answers, that any acidum may be concentrated in a body, and is there stronger, 

 or has its parts extended and diffused, and so weaker, so that magis et minus 

 vary the case much. To the last, which says all acida are volatilia, because of 

 an odour or scent that rises from them : he denies that all do give an odour, 

 and instances oleum vitrioli, which gives none; and by consequence no acida 

 pura afford it, but such as are mixed with an urinous salt. 



Dr. Voight goes on to prove, from his definition of salt, that spirit of wine 

 is no acidum, viz. because it has no vim attenuandi et resolvendi ; he means 

 properly and in its own nature, which consists in its inflammability, so that 

 spiritus vini, when it acts the part of a menstruum to dissolve bodies, does so 

 because of some salia volatilia that are mixed with it: for the more you impreg- 

 nate it with salt, the stronger menstruum is obtained. 2. He says sp. vini is 

 so far from agreeing with his definition of acids, in having vim coagulandi, that 

 it rather hinders it, e. g. acids coagulate milk : spirit of wine keeps it in a body 

 together, and hinders that coagulation. 3. Spirit of wine corrects acida, by 

 dulcifying spirit of salt and nitre, when mixed with them ; which are great cor- 

 roders of themselves. 4. Spirit of wine keeps bodies from degenerating into 

 acids ; thus, it preserves beer from souring. Also it prevents the fermentation 

 of vinum mustum, and the working of beer. 5. Acida give a red tincture to 

 syrup of violets ; spirit of wine does not change it. 



Thus far Dr. Voight. To the first proposition M. Kunkel replies, that since 

 sp. vini, according to his concession, abounds with salt, and is therefore a 

 menstruum, and can be sooner reduced to salt than oil, that for his own reasons 

 it may better derive its properties from salt, than from his imaginary oil. He 

 gives an experiment, viz. That sp. vini dissolves the crystals of silver; which it 

 could not do, he says, unless it consisted of an acidum et urinosum; for no 

 oleosa whatever can pretend to this effect. To his 2d proposition, that sp. vini 

 hinders coagulation, and to his instance in common milk, he says the contrary; 

 viz. That spirit of wine and milk in equal proportions will coagulate, as vinegar 

 and milk do. To the 3d, which is only an instance that spirit of wine dulcifies 



