PROCEEDINGS 1841—1848. 
191 
doubt of its great applicability for ventilating public buildings, the 
holds of ships, and also for mines. The construction was simple and 
economical, the space required small, and the current of air which it 
propelled exceeded that of any other application with which he was 
acquainted. Mr. Martin J. Roberts described a process of blasting 
by means of galvanism, which he had invented and adopted in Corn- 
wall, by which greater safety in firing gunpowder in mines was 
secured. 
Mr. William West, of Leeds, at the next meeting, called 
attention to a peculiar action of water upon a lead cistern. Mr. 
West had been requested to provide a remedy for the corrosion of 
certain cisterns at a gentleman's house. One of them had been five 
years in its present positiou, and in certain spots on the bottom the 
lead was gTeatly reduced in thickness. There were patches of 
efflorescent deposits of carbonate of lead, under which the lead was 
so soft as to be easily scraped with a nail into a hollow. For some 
time this phenomenon was very puzzling, but eventually Mr. West 
found that the water before reaching the cistern passed through an 
iron pipe which had become rusted, and he found that a portion of 
the rust being carried forward by the water into the cistern settled to 
the bottom, and caused the peculiar action which he described. 
Dr. James Inglis, of Halifax, contributed a paper by Mr. 
Simpson, the late curator of the Society, in which he gave the result 
of some observations which he had made in the- Stanley Shale and 
Flockton Stone or Fish Coal, Mr. Simpson's attention having been 
directed to the Fishes of the Yorkshire Coal Strata by a fine collec- 
tion presented to the museum by Mr. Embleton. He had examined 
the dark shale brought out in sinking a shaft at Stanley, in which he 
found not only detached teeth and scales of fishes but also numerous 
coprolites in the highest state of preservation. He also collected a 
number of similar specimens at Newton Lane-end, Grove Colliery, 
and Westgate Common. The shale containing these remains forms the 
roof of the Stanley Shale Coal, and is six or eight inches thick. i\.bove 
the six inches containing fish remains there are numerous examples of 
the dispersed remains of molluscous animals, and nodular masses of 
ironstone, rich in a small species of unio ; but they do not occur in 
