Xliv PROCEEDINGS. 



appearance a gtey-coloretl imul. In this condition it can of course be passed into- 

 moulds, subjected to pressure and forced to assume the shape of any design. 

 The .noulds like those employed in the making of pottery are of plaster of Paris. 



' ' At this stage in the process the scientific interest properly begins. If a portion 

 of the moulded mixture is allowed to dry it is as brittle as a cake of oatmeal. 

 Placed, however, in a kiln it becomes not only as hard as natural granite but a 

 great deal more tenacious. It is difficult to break it with a hammer. If the mass 

 be as tliick as an ordinary brick it will resist many heavy blows. The pressure 

 which it will sustain is enormous. In addition to this it is stated that the appli- 

 cation of water to the baked granite when hot will not cause it to crack. The 

 chief owner of the works told me he liad had one tile heated to redness on 14 

 successive days and placed while red hot in water. It was not cracked by any or 

 all of these tests. 



" But the process of making artificial granite does not simply illustrate the power 

 of heat as a rock-making agency. It does this admirably. But there is another 

 point of even greater interest, because I do not think it has ever before been sug- 

 gested, though here I may of course be in error. What makes the difterence 

 between red granite and grey ? The ' charges ' drawn from the kilns of the 

 Keene Artificial Granite Works answer this question. A difficulty not uncommon 

 in the ' firing ' of pottery and tiles has very naturally been encountered in the 

 granite making process. It is not easy to secure uniformity of temperature in 

 every part of the kiln. Hence arises lack of uniformity in the color of the bricks 

 and blocks of artificial granite. The majority are, as they should be, grey, pre- 

 cisely resembling the natural granite, and to be distinguished from the natural 

 stone only by close inspection ; but some are pink and some are red. These 

 colors are produced where the heat of the kiln has been most intense. I should 

 like to offer to the Nova Scotian Institute for their consideration and discussion the 

 suggestion based upon this fact — that the color of pink and red granites is to be 

 referred to the greater intensity of heat to which in the unequally heated kilns of 

 nature, they have been subjected — in other words that they are superheated grey 

 granites." 



Ordinary Mektinc, Province Building, 9th May, 1892. 



The President in the. Chair. 



Inter alia. 



A paper by Mr. A. Cameron, Principal of Yarmoixth Academy, entitled : — On 

 the visibility of Venus to the naked eye, was read by Prof. J. G. MacGregor. 

 (See Transactions, p. 148.) 



A paper entitled : — The Geology of Cape Breton : — the Lower Silurian, was 

 read bv E. Gilpm, Jr., A. M., F. G. S. (See Transactions, p. 167.) 



Alexander McKay, 



Becordimj Secretai-y. 



