182 On the Chemical Conslitution of 



dards appointed by the Act ; and after four years it shall he pe- 

 nal to cm])lov in trade or commerce anv meas'.ue or weight which 

 is not marked agreeahly to the directions of the Act. 



'' Tliat it be highlv penal for any person to make or sell mea- 

 sures and weights, but in compliance with the requisitions of the 

 Act. 



" That taldcs of equalization and reduction, of inches into 

 tenths of feet, ale and wine !j;alIons into standard gallons, &c. be 

 computed, an.d attached to the Act, as well as printed for sepa- 

 rate circulation : and that country schoolmasters,,who teach arith- 

 metic, be entitk'd to receive a copy of the Act of Parliament and 

 of these tables, from a prescribed parish officer — first gratuitously, 

 and afterwards at a fixed price. ; 



" Tliat suitai)le officers under t'he sheriffs of counties, mayors 

 of corporations, &;c., he appointed to read the Act at all fairs, 

 and once a mouth at markets, for five or seven years. 



" Tliat all former Acts, or clauses of former Acts, that are 

 either contradictory to one another or to this Act, be repealed. 



" That thejeijuisite exemptions be made in favourof goldsmiths 

 and apothecaries ; and in reference to the privileges of the cities 

 of Loudon and Westminster, the Founders' Company, &c. 



" That the effects of the proposed changes (slight as they are) 

 tqion the excise, taxes, rates, allowances, parochial customs, and 

 different branches of trade and commerce, be ascertained ; and 

 the manner of providing for them be carefully explained in the 

 Act." 



XXXII. OhservalioTis on. the Relation of the Laio of Definite 

 Proportions in Chemical Combination, to tlie Constitution of 

 the ylcids, Alkalis, and Earths. By .Iohn Murray, M.D. 

 Fellow oj the Royal College of Physicians, of the Royal So- 

 ciety of Edinltirgh, the Geological Societal of London, &c. ; 

 Lecturer on Chemistry, and Materia Medica and Pharmacy. 



[Concluded from p. 100.] 



i-HE compounds of nitrogen with oxygen present considerable 

 difficulties ; some of them are not easily obtained insulated; the 

 specific distinctions, therefore, which constitute the series, have 

 been variously represented, and the subject is still imperfectly 

 elucidated. Two of them, however, are determined with suffi- 

 cient precision, from which we may proceed — those constituting 

 the two oxides, the first, nitrous oxide, being composed of 10 of 

 nitrogen with 5-7 of oxygen ; the second, nitric oxide, of 10 of 

 nitrogen with 11-4 of oxygen. 



These combinations are conformable to the usual law of defi- 

 nite 



