1814.] On the Cause of Chemical Proportions. Si- 



Article V. 



EssaTj on the Came of Chemical Proportions, and on some Cir- 

 cuinstances relating to them : together ivilk a short and easy 

 Method of expressing them. By Jacob Berzelius, M.D. F.R. S< 

 Professor of Chemistry at Stockholm. 



(Continued from Vol. II, p. 454.) 



HI. On the Chemical Signs, and the Method of employing them 

 to express Chemical Proportions. 



When we endeavour to express chemical proportions, we find 

 the necessity of chemical signs. Chemistry has always possessed 

 them, though hitherto they have been of very little utility. They 

 owed their origin, no doubt, to the mysterious relation supposed by 

 the alchymists to exist between the metals and the planets, and to 

 the desire which they had of expressing themselves in a manner 

 incomprehensible to the public. The fellow-labourers in the anti- 

 phlogistic revolution published new signs founded on a reasonable 

 principle, the object of which was, that the signs, like the new 

 names, should be definitions of the composition of the substances, 

 and that they should be more easily written than the names of the 

 substances themselves. But, though we must acknowledge that 

 these signs were very well contrived, and very ingenious, they were 

 of no use ; because it is easier to write an abbreviated word than to 

 draw a figure, which has but little analogy with letters, and which, 

 to be legible, must be made of a larger size than our ordinary 

 writing. In proposing new chemical signs, I shall endeavour to 

 avoid the inconveniences which rendered the old ones of little 

 utility. I must observe here that the o!)ject of the new signs is not 

 that, like the old ones, they should be employed to label vessels in 

 the laboratory : they are destined solely to facilitate the expression 

 of chemical proporliuns, and to enable us to indicate, without long 

 periphrases, tiie relative number of volumes of the different consti- 

 tuents contained in each compound body. J>y determining the 

 weight of the elcnricntary volumes, these figures will enable us to 

 express the numeric result of an analysis as simply, and in a manner 

 as easily rcmenjbered, as the algebraic formulas in mechanical 

 philosophy. 



The chemical signs ought to be letters, for the greater facility of 

 writing, at)d not to disfigure a printed book. I'Lough thi^ hist cir- 

 cun)stance may not appear of any great importance, it ought to be 

 avoided whenever it can be done. I shall take, therefore, for the 

 chemical sign, the initial letter <f the Latin name of each elvvun- 

 tarij substance: but as several have the same initial letter, I shall 

 di-.tinguish them in the following manner : — I. In the class which 

 I call vietallii'uts, I shall employ the initial letter only, even when 

 this letter is common to the metalloid and to some luctul. 2. In 



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