66 Mr. Griffin on the Statical Relations of the Gases. 



Examples: — 1. Tho weight of 1000 cubic centimeters (= 1 Litre) of 

 oxygen gas is 100.000 x 1000 x .0000143236 = 1.4323G grammes. 



2. The weight of 500 cubic centimeters of nitrogen gas is 88.518 

 X 500 X .0000143236 = .63395 gramme. 



3. Proposed New Unit for Gas Measures. 



This unit is the bulk of a grain of oxygen gas, taken when Fahren- 

 heit's thermometer is at 60°, and the barometer at 30 inches. On 

 the assumption that a cubic inch of oxygen gas weighs .3418 grain, the 

 bulk of a grain of oxygen gas would be equal to 2.9257 — nearly 3 — 

 cubic inches. 



A gas jar containing 10 of these units, = 10 grains of oxygen gas, 

 would contain 29.257 — nearly 30 — cubic inches. 



A large receiver might contain 100 such units, r= 100 grains oxygen 

 gas, or 292.57 — nearly 300 — cubic inches ; being a little more than an 

 imperial gallon, which contains 277.274 cubic inches. 



All these measures should be divided into lOths and lOOths. 



If the decimal weights and measures were preferred, then we might 

 take for tho xmit of measurement, the bulk of one decigramme of oxygen 

 gas (= 100 milligrammes = 1.5438 grains); for the second measure, 

 the bulk of a gramme of oxygen gas (= 15.438 grains = 100 centi- 

 grammes); and for the third measure, the bulk of a decagramme of 

 oxygen gas (=. 154.38 grains = 100 decigrammes). In this case, 

 the temperature at which the gas is measured should be 0° Cent., and 

 the barometer pressure 0.76 meter. 



These measures would be about | larger than the proposed English 

 grain measures, the relation of the milligramme to the 100th of a 

 grain being that of .15438 to 1.0000. 



All the gramme measures should, like the grain measures, bo divided 

 into lOths and lOOths. 



Advantages peculiar to this Standard. 



The great advantage presented by this method of graduating Gas 

 Measures, is, that it shows, distinctly and readily, the absolute weight 

 (either in grains or grammes according to the standard adopted) of 

 any quantity of any gas submitted to trial As all the vessels are 

 graduated to 100 degrees, and as the atomic weight and the specific 

 gravity of oxygen gas are both fixed at 100.000, it follows that, in 

 order to estimate the absolute weight of a measured quantity of a gas, 

 all we have to do is to multiply the degree which marks the measure 

 by the number which indicates the specific gravity. There is, con- 

 sequently, only a single multiplication to perform, whereas, in all 

 the cases cited above, there are two multiplications required, neither 

 of which can be avoided. The only precaution necessary to be taken 

 in making the calculations, is to place the decimal point in the proper 

 place. It is scarcely necessary to add, that the multiplications can 

 be facilitated by the help of logarithms. 



