v Mr. Montgomery on a New Self-Acting Railway Break. 225 



Analysis of tho water of the Brock Burn, by Professor Penny :— 



Organic matter, 1.150 



Carbonate of Hine, 3.610 



Sulj.li.itt> of lime, 0.870 



Common tali 0.881 



Sulphate of potash and soda, 0.299 



■ncsia, 0.120 



Oxide of iron, 0.070 



Silica 0.150 



7.150 

 Mr. Stirrat of Paisley, on being invited to give his opinion on this subject, 

 spoke in the strongest terms of the capabilities of the works. In regard to 

 the rain-guage commonly in use, he stated that it did not show one-half of 

 the quantity of rain falling. When it was set on a height, like the one 

 in the College, the rain falling during a storm was not correctly indicated. 

 Ee had kept one for fourteen years, and set up one beside it at a height 

 of four feet ; and he found that, in a storm, there was a difference of 30 

 per cent, in favour of the lower one. He had no doubt that the rain 

 falling in this part of the country averaged 56 inches. This opinion he 

 formed from three years' measurement of the reservoir at Paisley, which 

 showed 52 inches for each year, while the rain-guage indicated only 33. 

 He considered that, as the works of the Gorbals Company now stood, 

 they could afford an abundant supply of water to 270,000 of a population. 



Explanation of Plate— The conduit which conveys the water from the reservoirs 

 is from 400 to 500 jards in length, and constructed of arched masonry. At the end of 

 the conduit next the reservoir, there is situated a self-acting sluice, differing in 

 construction from the one shown in the plan, but acting in concert with it. The self- 

 acting sluice shown in the plan is placed at the end of the first filter, and is connected 

 by a lever with the float in the well. The water from the reservoir passes along the 

 continuation of the conduit at the upper end of the series of filters, and flows in a regular 

 ami thin stream into the first filter, which consists of gravel, through which it percolates, 

 and then rises within the double wall which separates the first from the second, or 

 coarse sand filter, and so on till it reaches the tank, as shown in the transverse section 

 of filters. 



The use of the self-acting sluice is to prevent the continued flow of water into the 

 filters after the tank lias been filled, and it acts in the following manner: — at the bottom 

 of the well containing the float there is a pine connecting the well with each of the tanks, 

 whereby tho water m the u. 11 ami that in the tank, which may be in use at the time, 

 is always kept at the same level, as the float rises with the water in the well it acts upon 

 tho sluice, by shutting it, thus preventing the water from passing onward. The water 

 nted from passing into tho filters, accumulates in the conduit, until it begins 

 to act on the self-acting sluice at the reservoir, which in turn shuts off the supply of 

 water from that source. It is c\i<lcnt from this that the supply of water from the 

 reserve. ir must he regulated by the demand at the distributing tank. 



Mr. Robert Montgomery of Johnstone exliil tit ed and explained his new 

 Self-Acting Railway Break. 



The friction or break wheel, which was nearly of full working size, was 

 17 inches in diameter and 2J broad; the full-sized wheel would be 18 



