9 S IMPROVED FISHERY HARBOUR ACCOMMODA TION 



No concrete must be made during frost. 

 It is thoroughly to be mixed in a machine, and Mr. 

 Massent's is mentioned as performing twelve revolutions. 



IRON CONCRETE. 



At Stranraer Pier, constructed of timber, Mr. Leslie 

 introduced a concrete consisting of gravel and iron borings. 

 Mr. John Howkins, junr., resident engineer, states " the 

 quantity of iron borings mixed with the hearting was 160 

 tons, and taking the weight of the gravel at 20 cubic feet 

 to the ton, the proportion of borings to gravel' in weight 

 is I ton of the former to 17 of the latter, and the proportion 

 in bulk, i to 34, assuming 10 cubic feet of iron borings to 

 weigh one ton (which, however, I have not the means of 

 ascertaining at present). 



" In digging down at the end of the pier, where the gravel 

 and borings have been acted upon by the sea for two and a 

 half months only, I found the layers of borings caked in 

 a hard mass, and particles of gravel and sand adhering to 

 the sides of the layers ; showing that the concretionary 

 influence of the borings is extending, and will, in all 

 probability, in course of time completely bind the inter- 

 vening layers of gravel." 



ASPHALTIC MASONRY AND CONCRETE. 



" I have lately tried," says Mr. Stevenson, " at the 

 island of Inchkeith some experimental masonry cemented 

 together with British asphalte. At the same time, the 

 experiment was successfully tried of letting down under 

 the surface of low water, stones and hot asphalte placed in 

 canvas bags, which were pressed down upon the irregular 



