VOL. IX.] PHILOSOPHICAL TRANSACTIONS. 1 63 



by the former method, is mild and gentle, its taste approaching somewhat to- 

 wards that of acids; whereas the other, which has passed through the violence 

 of fire, has not the least affinity therewith, and can almost as little be endured 

 by the tongue as a live coal of actual fire. And there being very many degrees 

 of heat, whereunto the tartar may be successively exposed, according to the said 

 degrees, the manner of applying it, the space of time, and the substances 

 employed in its calcination ; the result will be different, and produce different 

 effects : and the very same sort of tartar will oftentimes become sensibly differ- 

 ent upon these methods of procedure,' and produce most of the appearances 

 mentioned by Tachenius. And sometimes several parcels of tartar, which seem 

 to our taste and eye calcined to the same degree ; yet the operations in nice ex- 

 periments are frequently various. And to me it does not seem so very wonder- 

 ful, that many concretes do really differ, which to the senses appear simple and 

 uniform; of which many causes may be assigned. A great number and variety 

 of instances might be here introduced, to clear this truth, if it were not already 

 sufficiently known and believed. 



But to proceed where I digressed ; what I have asserted, is confirmed by the 

 great variety, which is most visible in pot-ashes : some, being highly alcalizate, 

 are fiery hot ; others cold, watery, nitrous to the palate, and no less weak in 

 effects than taste ; whereof soap-boilers, dyers, and other mechanics are very 

 sensible. All which proceeds from the woods, being, when they are burnt, 

 green or dry; from their abounding with oily, aqueous, or acetous parts; as 

 also from the several degrees of heat employed in their production. Those who 

 make glass, and especially the finer sorts, complain, that they cannot, with 

 the same quantities and proportions of ingredients, always produce the same 

 sort of glass: which they, not without reason, ascribe to the differences in their 

 ashes. This must necessarily often happen according to the above mentioned 

 hypothesis. 



An Account of some Books. N° 107, p« ISQ. 



I. Erasmi Bartholini de Naturae Mirabilibus Questiones Academicse. Haf. 

 1674, in 4to. 



The subjects of these disquisitions are twelve, viz. 



I. The figures of bodies in general. — 2. The figure of snow. — 3. The pores 

 of bodies. — 4. Attraction. — 5. The Cartesian physiology. — 6. Experiments. — 

 7. Physiological hypotheses. — 8. Custom. — 9. Nature. — 10. The study of the 

 Danish tongue. — 11. Judgment and memory. — 12. The secrecy of sciences. 



II. Thomas Bartholini de Anatome Practica ex Cadaveribus morbosis ador- 

 nand'A Consilium. Haf 1674, in 4to. 



y 2 



