S20 Description of a Machine for pumping IVater 



these, it seems that there are three distinct comhinations of 

 platina with sulphur. The suh-sulphuret appears to con- 

 tain one proportion of sulphur, the super-suljhuret two 

 proportions, and the sulphuret one proportion and a haif. 

 The results which would be furnished from calculations of 

 this kind, do not differ materially from those actually ob- 

 tained. 



The quantity of sulphur which combines with 100 grains 

 ■ tf platina in these several compounds I have here annexed, 



Grs. of Platina. Sulphur. 



r 1 9-04 "^ Sub-sulphuret * 

 100 < 28-21 VSulphuret 



(.38'8oJ Super-sulphuret. 



[To be continued.] 



XL. Description of a Machine for pumping JVater used 

 in the East. By M. Chastellan, ^aiAor o/'" Travels 

 in the Moreaf." 



jL he art of irrigation ought to be better understood in 

 countries which are subject to drought, than in those where 

 abundant and periodical rains seem to render irrigation less 

 necessary: there are circui;isiances nevertheless under 

 which it is desirable, even in European countries, to prcicure 

 an abundant and judicious distribution of water: and the 

 expense of a machine with the necessary reservoir for this 

 purpose will be speedily recompensed. 



Watering by hand-engines is frequently disadvantageous, 

 and always tedious. If the gardener has a large piece of 

 ground to manage, he must necessarily water it during the 

 heat of the day, for he cannot have sufficient lin)e before 

 sunrise or afer sunset. Besides, the water which he 

 employs for this purpose being newly drawn from a 

 well, or having been contained in deep reservoirs, it 

 cannot get rid of its loo great coolness, or of that crudity, 

 which are so injurious to plants; whereas the same water 

 contained in large reservoirs and in uncovered canals for 

 irrigation, soon acquires the temperature of the atmosphere, 

 and the properties of rain water. The way in which the 



* I am aware that the nomenclature here adopted is defective, and founded 

 on an erroneous primiplc; that there is an excess, a deficiency, a neutraljjoint 

 in these cimibinations It gi^-e^ no information concerning the proportions 

 of the constituents of the compounds. Protestor Berjielius, 1 believe, intends 

 shortly to publish some Obiervuiiuns on the Chemical Nomencl.iture, in 

 which these deficiencies, I have no doubt, will be happily supplied. 



•j- Bib. Phtji. ICcoii, Dec, iiiiJ. 



water 



