An Account of a Book

when I washed away, I found Globules of Mercury in many places under the Bronchia, and upon Examination they proved to be in the Arteria pulmonalis. I have press'd these Globules backwards and forwards, and made some of them get out at the holes made in the Vesicule above describ'd. I took some pains to find where the Sanies was received into the Bronchia, but could not satisfy myself. From hence may appear the danger of using Mercury in humane Bodies, so as that it may get into the Mass of Blood, especially into the Lungs; they wanting that brisk strong motion which the Muscles have in other parts, which are able to force it along with the Blood, in order to the raising a Salivation. Their lax spongy Texture makes them extremely unfit for clearing themselves of so troublesome a Guest as Mercury is. That it has this Effect on humane Lungs, is plain from what we daily see in persons that have been often-flux'd, who are after observ'd to dye of Consumptions that will not give way to Medicine. Medicina Hydrostatica, or Hydrostaticks applied to the Materia Medica, shewing how by the Weight that divers Bodies used in Physick have in Water, one may discover whether they be Genuine or Adulterate. By the Honourable ROBERT BOYLE, Fellow of the Royal Society, London, 8vo 1690. Printed for Sam. Smith. The Honourable Author designs in this Treatise to shew, that by weighing Bodies in Water, comparing their weight in Air, and from thence deducing the proportion of weight to Water, the Specific Gravity of Bodies may be more exactly determined; counterfeits distinguished from Genuine, and the mixture of mineral Particles in Stone discovered. Archimedes first observed, That a Body heavier than Water, weighs less in Water Water than in the Air, by the weight of as much Water as is equal to it in Bulk. The difference then of the Weights in Air and Water, gives the weight of so much Water, and dividing the greater number by the lesser, the Quotient compared to unity, will be the proportion of the Weights of the solid Body and Water. Rock Crystal, and the Icicles of Vaulis are us'd as the Standard, (being the most homogeneous and simple) to compare other Stony Bodies with, which if found heavier are presum'd to contain matter heavier in specie. They are to water as $2\frac{3}{4}$ to 1. Lapis Hematites almost double to the Standard, and Iron is discover'd in it by the Styptical taste of its Flowers, and by the black colour when mixt with Galls. Lapis Lazuli having a vomitive Quality as 3 to 1. Loadstone more than 4 to 1. Lap. Calaminaris, us'd in the turning Copper into Brats, and of a Quality very restringent, appears to weigh as almost 5 to 1. Coral, truly therefore esteem'd a Lithodendron somewhat exceeds Crystal. Pearl near the weight of Crystal. Calculi Humani and Bezoars (Animal Concretions) amount not to twice the weight of Water, and are by a fifth part lighter than Crystal, by which counterfeit Bezoars are detected: such an one being found as heavy as a mineral. It is further observed that counterfeit Crabs Eyes are of much more weight than natural. False Stones are easily detected, the Mineral which gives the Colour making them preponderate to true Gems. False Coyns in this manner are easily discoverable. Our Author having in these particulars shewn in what manner all solid Bodies heavier than Water may be compar'd to one another, and not only their Specific Gravity, but their qualities very often detected; comes now to consider and propose, 1. How Bodies lighter than Water may be examined in it, viz. by adding Lead to Wax or Fir-wood, and subduing for the heavy Body so added. 2. How Fluids, as Mercury, or Chymical Oyls of Cloves, &c. or Bodies dissoluble in Water, as Sublimate, Alum, Vitriol, Vitriol or Fragments of any brittle Body, viz. by a little Glass Bucket or Viol stopt, which may receive these Bodies, adding so much Water as will fill the Spatiola of the Fragments, up to the brim of the Glass; for which allowance must be made in the computation of the weight, both in the Air and Water. Sublimate which wants its due proportion of V will be this way discover'd, and Roman Vitriol mixed with Alum. It is here observ'd that V is to water as 14 to 1. But the more easy and simple Method of weighing Bodies dissoluble in Water, is to use the thinner Oils, such as Oil of Turpentine of the first rise in distillation. Having hitherto examin'd Bodies by Water and Oils, our Author proceeds to examine the weight of Liquors by weighing Solids in them. For if a heavy Body in Water lose so much of its weight as the quantity of Water weighs that is of an equal bulk to the Body, the proportion of the weight of all Liquors will be easily obtained. For instance, A piece of Amber of between 3 and 4 Drams weighed in Water 6 ½ gr. in Red French Wine 8 ½ gr. in Brandy 17 ½ gr. in rectified Spirit of Wine 34 ½ gr. This way may be apply'd to compare all sorts of Liquors, as Wine in the Must, Mature, decaying, vapid. Juices of Herbs, Beer, Sider, &c. But Acids are heavier than Water. Hence the Degrees of their acidity may be observed. Of Waters, Rain Water seems the lightest, and scarce a 1000th part difference discover'd in any of them. This is particularly apply'd to the famed Water of Ganges, tho Travellers assert an extraordinary lightness in it. In the last place the bulk of solid Bodies may be found out by this Method. For since a Cubical Inch of Water weighs 256 gr. and as much of Oil of Turpentine 221 gr. if a Body of any magnitude and irregular shape lose so much or more times that weight in Water or Oil, it is of a Magnitude equal to one or more Cubical Inches. In the subjoyn'd Tract, our Author treats particularly of Minerals, and observes that Emery is as 4 to 1 to Water. Jet lighter than Crystal; so is Fufil Amber, Sulphur Vive, English and Venetian Talk. In an American Talk heavier than Crystal, a Metallic Substance was observ'd. Fine Gold is as 19 to 1 to Water. Hence any Fallacious Mixture us'd by the Negroes in Gold-pan may be observ'd. Brass is not quite half so heavy as Gold, &c. The whole Book is made up of curious Remarks and Experiments, such as usually proceed from its renowned Author, whose single Name is more than sufficient to recommend it to the perusal of the Studious Naturalist. FINIS.