VOL. VI.] PHILOSOPHICAL TRANSACTIONS. 647 



winders, capstans, rollers, wheels of engines, with or without teeth, boarers, 

 cranes, &c. with the reason and measure of their force ; as likewise the wheels 

 of coaches, carts, or waggons, with the reason of divers circumstances in the 

 fabric and use of them. Of pulleys ; of the measure and reason of their strength. 

 Of screws; with the reason of their great force, and the measure of it; as also, 

 the measure of the length of the spiral line about a cylinder, whence the screw 

 takes its rise, and of the solid content of the screw. Of the composition, 

 acceleration, and retardation of motions ; and the motion of projectiles, 

 with the nature of the lines described by such motions. Of percussion or 

 striking; with the measure and effects of blows, or strokes, according as the 

 bodies striking do differently occur one to the other, and the centre of force in 

 such percussion. Of the wedge, with the reason and measure of its force. Of 

 repercussion, resilition, or reflection of bodies, which he derives from the 

 spring or elastic virtue in them : Of hydrostatics, with the reason and measure 

 of sinking or swimming of heavy bodies in a fluid : Of the weight and spring of 

 the air, and the counterpoise of the atmosphere ; from whence he derives those 

 effects which were wont to be ascribed to the fuga vacui, or nature's abhorring a 

 vacuity; with the explication and reason of the several phaenomena of the 

 Torricellian experiment, and others of like nature, and of the very great con- 

 traction and expansion of the air: Of raising a great weight with a man's breath, 

 blowing a bladder. And the solution of divers other mechanical questions. 



II. Danielis Ludovici, Medici Ducal. Saxo Gothani, de Pharmacia Mo- 

 derno Seculo applicanda, Dissertationes III. Gothae, 1 67 1, in 12mo. 



A pharmaceutical treatise, an account of which cannot be interesting to the 

 medical reader of the present day. 



III. Job. Bapt. Sylvatici Institutio Medica de iis qui Morbum simulant de- 

 prehendendis. Francofurti ad Masnum. An. 167], in 12mo. 



A dissertation on feigned diseases, and on the methods of detecting such 

 impostures. 



IV. Quadripartitum Botanicum Simonis Pauli Medici Regii in Dania Ar- 

 gentorati, in 4to. 



The learned author undertakes, in this work, to describe chiefly the uses and 

 virtues of those simples or plants, which growing in Europe, are by long ex- 

 perience approved of ; treating more particularly of those that grow in Den- 

 mark and Norv/ay. 



This description he performs in such a method, that he reduces the said 

 plants to four classes alphabetically, according to the four seasons of the year 

 wherein they grow or are in flower; that so it may be known when such and 

 such plants are to be had and gathered for use ; beginning from the winter 



