.C O N :T E N T S. V 



Short hidory of the invention and ufe of the pendulum, with a moveable cftnfre of fufpenSon. In- 

 effedlual endeavour to ufe Whitehurft's machine. Account of various inrtruraents for determining 

 the weight and mcafure of determinate quantities of water. Metallic cube and cylinder. Scale 

 of equal parts, with apparatus and method of ufing it. Hydroftatic balance and weights. Opera- 

 tions for determining the folidities of the cube and cylinder. 



II. Letter from Dr. Beddoes, refpefting Citizen Fourcroy's Account of the Dif- 

 coveries of Maj'ow - - - " P- io8 



Confiderable inaccuracy in Citizen Fourcroy's general eftimate of the mental powers of Mayow. 



III. Obfervations and Experiments on various feponaceous Compounds, parti- 

 _ cularly the Fifh Soap of Sir John Dah-ymplc. By Mr. Robert Jamefon, 



F.L.S, &c. - - - - - p. 108 



Short hiftory of foap. Methods of making the different kinds, white, mottled, yellow, foft. Con- 

 tents of the wade leys. Soap of whalerXiil. Sir John Dairy mple's foap of fifh. Obfervations on 

 the fatty matter into which water converts mufcular fibre. Detail of experiments on the foap of 

 fi(h, made at the requeft of the board of truftees at Edinburgh. Soaps of wool, of glue, of peat. 

 Neither the mufcular fibre, nor wool, nor glue, will unite with tallow and alkali, in the common 

 procefs for making hard foap. Peat foap gives a brown colour to cloths. Antifeptic power of 

 alkalis. 



IV. Experiments and Obfervations to prove that Snow does not contain Ox}'gen 

 either in Sokition, or in Combination, and that its fertilizing Quality does not 

 depend on this Caufe. By Dr. Joachin Carradori de Prato - p. 1 19 



HafTenfratz having inferred that fnow contains oxigen, the author made experiments with frefh 

 water fifh. They died immediately in fnow water, which had not been expofed to the atraofphere ; 

 though the fame water was by a ihort expofure rendered fit for the refpiration of fiflies. Snow 

 water does not emit oxigen by folar light, and does not therefore contain that fubftance in 

 combination. 



V. On certain Properties of Strontian and Barytcs. By Citizen Vauquelin p. 122 



Strontian, as well as barytcs, is difpofed to combine with filex and with alumine, which they render 

 foluble in water. ' Barytes combines by double affiniiy with oil, and forms an infoluble foap : it 

 ?.!fo combines direflly with animal fubftances in the humid way. From thefe properties it is 

 inferred that ftrontian and barytes ought to be clalTed with the alkalis, and may be ufed for 

 flmilar.purpofes, &c. 



yi. Concerning thofe perpetual Motions which are producible in Machines by 

 ■ the Rife and Fall of the Barometer, or by the Thermometrical Variations in 

 the Dimenfions of Bodies. (W.N.) - - - p. 126 



Short enumeration of fuch natural powers as afford perpetual motions. Defcription of the barome- 

 trical clock in Cox's mufeum. Other methods of applying the barometer to fimilar purpofes; . 

 Thermometers, fluid and folid. Conftruftion of felf-moving wheels by expanfion-bars. 



J 



VII. Chemical Confiderations on the Ufe of the Oxides of Iron in the dyeing of 

 Cotton. By J. A. Chaptal. (Concluded from p. 93) - P- ^29 



Nankeen colours. Violet from madder and iron. Peculiar management, Obfervations on afirin- 

 gent vegetables, particularly galls. 



VIII. Ac- 



