688 PROF. C. P. SMYTH ON THE REPUTED METROLOGICAL SYSTEM 



same temperature. But the other station, though inside the Pyramid, is 140 feet 

 above the ground outside ; it is therefore also right that its temperature should 

 be less, perhaps about 22°. 



But this temperature was raised unnaturally by the presence of Arabs and 

 their torches, and by the absence of watery vapour. Referring therefore to the 

 same philosopher's measure of the temperatures of the great Joseph well in the 

 citadel of Cairo, — and where there was probably rather too much watery vapour, — 

 and finding him give that temperature as 17° or 18° centigrade, — we may suspect 

 that the mean between these two and what was observed in the King's Chamber, 

 at least to the nearest even degree, would be the true result for that chamber 

 under normal circumstances. 



We conclude, therefore, from thence, that the Pyramid constant is 20° centi- 

 grade ; or, 68° Fahrenheit. But, the note worthy of remark about that par- 

 ticular point is, that it defines what may be called a temperature of ^th; i.e., 

 |th the distance between freezing and boiling, upwards from the freezing point ; 

 exhibiting again in the most unexpected manner, the typical division of the Py- 

 ramid. Hence there can be little hesitation in adopting 68° Fahr. ; and inasmuch 

 as one English cubic inch of distilled water w^eighs 252458 English grains at a 

 temperature of 62° Fahr., and Barometer at 30 inches, — the coffer, measuring 

 70,970-2 English cubic inches, would weigh 17,917,000 English grains, with the 

 contained water at that temperature. But reducing the weight of the water from 

 its density at 62° to that at 68°, the quantity becomes 17,905,500 English grains. 



This, therefore, is the total weight of the Pyramid's grand standard of weight 

 measure ; excepting my own possible errors of reduction. 



(9.) Pyramid Weights and Measures. 



With the capacity of the coffer, its water-weight, and the linear standard, as 

 already determined, we have now to see what sort of a commercial and scientific 

 system of measures they are capable of affording, and for small as well as for 

 large quantities ; especially, too, in how far such a Pyramid-derived system may 

 agree, and in how far it may differ in the subsidiary items, from what is at pre- 

 sent in use in Great Britain. 



The chief point of difference will evidently be in the divisors ; for the Pyramid 

 can acknowledge of little beyond fives and times of five ; and they are not found 

 frequently in the British system. Nevertheless, it is remarkable to see in how 

 many instances the two arrangements approach each other ; and that in some 

 cases, where a closer approach might have been desirable, it is found by appealing 

 from the " Imperial System" of George IV. to the ancient British weights and 

 measures. 



