This Treatise will be dispatched within a very short time, and would have been so, ere this, if the extremity of the late Frost had not stopt the Press. It will be accompanied with some Discourses of the same _Author_, concerning _New Thermometrical Experiments and Thoughts_, as also, with an Exercitation about the _Doctrine of the Antiperistasis_: In the former whereof is _first_ proposed this _Paradox_, That not only our Senses, but common Weather-glasses, may mis-inform us about Cold. _Next_, there are contained in this part, New Observations about the deficiencies of Weather-glasses, together with some considerations touching the New or _Hermetrical_ Thermometers. _Lastly_, they deliver another _Paradox_, touching the cause of the Condensation of the Air, and Ascent of water by cold in common Weather-glasses. The latter piece of this part contains an Examen of _Antiperistasis_, as it is wont to be _taught_ and _proved;_ Of all which there will, perhaps, a fuller account be given by the Next. {10} * * * * * _An Account of a very odd Monstrous Calf._ By the same Noble person was lately communicated to the _Royal Society_ an account of a very Odd Monstrous Birth, produced at _Limmington_ in _Hampshire_, where a Butcher, having caused a Cow (which cast her Calf the year before) to be covered, that she might the sooner be fatted, killed her when fat, and opening the Womb, which he found heavy to admiration, saw in it a Calf, which had begun to have hair, whose hinder Leggs had no Joynts, and whose Tongue was, _Cerberus_-like, triple, to each side of his Mouth one, and one in the midst: Between the Fore-leggs and the Hinder-leggs was a great Stone, on which the Calf rid: the _Sternum_, or that part of the Breast, where the Ribs lye, was also perfect Stone; and the Stone, on which it rid, weighed twenty pounds and a half; the outside of the Stone was of Grenish colour, but some small parts being broken off, it appeared a perfect Free-stone. The Stone, according to the Letter of Mr. _David Thomas_, who sent this Account to Mr. _Boyle_, is with Doctor _Haughteyn_ of _Salisbury_, to whom he also referreth for further Information. * * * * * _Of a peculiar Lead-Ore of _Germany_, and the Use thereof._