Experiments on the Expansibility of Stone. 207 



2. On the Expansibility of different kinds of Stone. By 

 Mr Alex. J. Adie, Civil Engineer. 



This paper contains the results of an extensive series of experi- 

 ments made upon different kinds of stone, as well as upon iron and 

 upon brick, porcelain, and other artificial substances. The instru- 

 ment employed was a pyrometer, of a simple construction, capable 

 of determining quantities not greater than — of an inch. The 

 length of the substances generally employed was 23 inches. The 

 general result of these experiments is, that the ordinary building 

 materials of stone expand but very little differently from cast-iron, 

 and that, consequently, the mixture of those materials in edifices is 

 not injurious to their durability. The experiments from which the 

 expansibility of the substances was numerically determined, were 

 made between the limits of ordinary atmospheric temperature and 

 that of 212°; steam being introduced for that purpose between 

 the double casing of the instrument. 



The following results were obtained for the fractional expansion 

 of the length, for a change of temperature of 180° Fahr. : — 



Table of the Expansion of Stone, fyc. 



Decimal of length 

 for 180° Fahr. 



1. Roman Cement, . . 0014349 



2. Sicilian White Marble, 00 1 1 04 1 1 



33 Carrara Marble, 0006539 



4. Sandstone from the Liver Rock of Craigleith Quarry, .001 1743 



5. Cast-iron from a rod cut from a bar cast 2 inches square, .00114676 



6. Cast-iron from a rod cast half an inch square, . . .001 102166 



7. Slate from Penrhyn Quarry, Wales, . . . .0010376 



8. Peterhead Red Granite, 0008968 



9. Arbroath Pavement, 0008985 



10. Caithness Pavement, 0008947 



11. Greenstone from Ratho, . . . . . . .0008089 



12. Aberdeen Gray Granite, 00078943 



13. Best Stock Brick, 0005502 



14. Fire Brick, 0004928 



15. Stalk of a Dutch Tobacco-pipe, 0004573 



16. Round rod of Wedgewood Ware (11 inches long), . .00045294 



17. Black Marble from Galway, Ireland, . . -00044519 



9Hth April. — Sir Thomas M. Brisbane, President, in the 

 Chair. The following communications were read : — 



1, On the Action of Voltaic Electricity on Alcohol, Ether, 

 and Aqueous Solutions. By Arthur Connell, Esq. 



% A Review of some of the more important Physical Truths 

 contained in the writings of the Greek Philosophers, 

 preparatory to an attempt to show that the more an- 

 cient language of Greece was based upon the Truths of 

 Natural Philosophy. By the Rev. Archdeacon Wil- 

 liams. 



