CONTENTS. 



SUPPLEMENT. 



Engravings of the following Obje&s : 1. A new Air-Pump, by Mr. Wright 

 or America; 2. New Valve and Parts of a condenfing Syringe for the Gales, 

 by Mr. Cuthbertfon, with which Mr. Northmore's Experiments were made ; 

 3. A very fimple and improved Graphometer, by Mr. Banks. 



*■■-. 

 I. A Defeription of an Air-Pump upon a new Conftruclion. By Elizur 

 Wright. Communicated by Benj. Silliman, Eiq,. Profeflbr of Natural Phi- 

 lofophy, &c. in Yale College, Newhaven, America. - Page 305 



%t, Concerning the State in which the true Sap of Trees is depoiited during 

 Winter. By Thomas Andrew Knight, Efq. - - .30ft 



III. Singular Method of forming Walls and Roofs of Rural Buildings in In- 

 doftan. Communicated by xM. Legoux de Flaix, Officer of Engineers. 313 



IV. Account of fome new Improvements in Steam-Engines. By Mr. Arthur 

 Wcoff, - - - - 310 



V. On the Magnefian Earth of Baudiflero. By M. Giobert. - 3?0 



VI.* Firft Communication on an artificial Tan prepared from Coal, chared 

 .Wood, refinous Subftances, &c. Abridged from the Original of Charles 

 Hatchetr, Efq. F. R. S. • - - - 327 



VII. Memoir on the Bifcovery of a factitious Puzzolana, pre fen Jed to the 

 French National Inftitute by M. Dodun, Engineer in Chief of Bridges and 

 Highways in France, - - - - 331 



VJJL Experiments and Obfervations upon the Contraction of Water by Heat 

 at low Temperatures. By Thomas Charles Hope, M. D. F. R. S. Ed. 

 jprofdtbr of Chemiftry in the Univerflty of Edinburgh. From the Edinburgh 

 Philoibphical Tr;mlaclions for 1801. - - - 339? 



JX. Obfervations en Turf, from the German Rathbeger fur alle Stamd. By 

 Doflor C\)i)tnbuf.:h. - * - - , * 304 



X. 'Experiments on the remajknble Effects which take place in the Gafes, by 

 Change in their Habitudes, or elective Attractions, when mechanically com- 

 pelled. By 1 honns Noithmore, Efq. In a Letter from the Author. 36$ 



XL Account of a Graphometer for measuring the Angles of Cryftals In a 

 Letter from Mr. Robert Bnncks, No 411, Strand. *" - 374 



Account of new Boole?, 316.— -Phil of jphical TranfadYions of the Royal Society 

 of London for tSOj, Part II. ib, — Tranfaclions of the Royal Society of 

 Kdinbu gh, (being the Continuation of Part II. together with Part III. of 

 fhl Fifth-Volume), fei' ■ ■ ! 37T 



