An Extract of a Letter from Mr Ralph Thoresby, F. R. S. to Dr Nehemiah Grew, Fellow of the College of Physicians and R. S. concerning a Ball Voided by Stool

post 5 quantum conjectare potui illa sex fermè digitorum spacio obscurata fuit. Eam vidi per intervalla usque ad horam quintam cum 35 min. quo tempore deerant ad summum 3 min. à totali ejus immersione, tunc autem parva Nubes sed densa ita Lunam operuit, ut eam amplius non viderim & quamvis maxime intentus fuerim, ut si fieri posset ejus Emersionem viderem nullomodo mihi licuit tum ob crassitiam Vaporum qui erant circa Horizontem, tum ob diei adventantem lucem eam oculis cernere. Ab initio usque ad tempus Immersionis Luna mihi conspicua facta est plusquam Vigesies, sed propter intercurrentes Nubes, & breve temporis spatium quo eam intueri licebat penes me non fuit quidquam exæste, satis definire at quamvis hæc Observatio utilis valde esse non possit ad Lunarios numeros expendendos, illa tamen sufficit ad curiosis satisfacendum eosque convincendum illos numeros non multum a vero aberrare. VI. An Extract of a Letter from Mr Ralph Thoresby, F.R.S. to Dr Nehemiah Grew, Fellow of the College of Physicians and R.S. concerning a Ball voided by Stool. A Poor Apprentice Girl at Rawden, 4 miles from Leeds in Yorkshire, about 14 years of Age, having been tormented with Colical, and, as was suppos'd, Nephritick Pains for some time; at length voided a roundish Ball, per Anum, as hard to feel upon as a Stone. After a while, the Pains returning with greater violence, so as to make her roll upon the ground, she voided another as hard, and much bigger. Upon which, one Mrs Ward a neighbouring Gentlewoman, who had been much afflicted with Gravel, gave her some of those Medicins which she us'd to take her self. Whereupon the Girl voided a third Ball, also per Anum, with less pain, yet the greatest of the three. The first of these Balls is smooth and glossy, of the colour of a right Hazel nut, 3 inches about, and somewhat compressed. The other two rough and gritty, and in like manner a little compressed into a kind of obtusely triangular figure. The 2d, is 4 inches and a half round about; the last, 5 inches and a half. Considering their bulk, all 3 are very light, especially the 2 latter and greater ones, of which the last weighs but 5 Drams 36 Grains; and both of them swim in water. This lightness proceeds from the Matter whereof they consist; which, in some places is purely Downey or Fuzzy; in others, mixed with a Gritty substance, yet not confusedly, but regularly mixed. The Fuzzy parts possess the central part of the Ball, with a small particle of blackish Glass or other Vitrify'd substance in the very Centre itself. Over which are several Coats, gritty and fuzzy, alternately ending in the circumference with a grit, much resembling the Ground-work and Superstructure of the Oriental Bezoar-stone. The Powder of one of these Balls scraped off with a Knife, is no way mov'd or affected with any sort either of Alcaline or Acid Liquor dropp'd thereupon. Neither being burn'd doth it stink, it consisteth therefore of no Animal substance; but the Girl being of the Green-sickness age, the gritty parts (with the glassy particle in the Centre, as the most ponderous and least moveable) seems to be broken off of Tobacco-Pipes, and ground small between her Teeth; the downy or fuzzy to be lick'd or scraped off the Lean of Mutton, or the Rind of Peaches, or some other Part or Plant. Her Stomach kneading the Matter into a Coat, as her changeable Appetite supply'd it alternately with one or the other sort.