ON THE STEERING OF SCREW-STEAMERS. Ill 



'Name of Member of Cbmmittee asking for information, Mr, C. E. DeEanee, 

 F.G.S. 



Name of Individual or Company applied to : — • 



Mr. Matthew Brown. 

 1. Pole-Street Breweiy, Preston, Lancashire. 3. 123 feet. 3. 90 feet, diameter 

 4 feet. 4. 12 feet G inches before, 5 feet 1 inch after, and rises to 12 feet 6 inches 

 in 40 minutes. 5. 1015 gallons per hour. 6. No. 7. No. 8. Cannot tell, inas- 

 much as there is a small supply of water at a higher level than the main spring ; 

 and this small supply when analyzed contained 30 per cent, of saline and mineral 

 im]Durities, the mineral being chiefly iron ; and I estimate this small supply, apart 

 from the main spring, would fill a pipe of 1 inch diameter, continually falling into 

 the bottom spring or well. 12. No. 13. No. 14. No. 15. No. 



APPENDIX. 



The information collected by Mr. Moore, F.G.S., in the Bristol, Bath, and , 

 Radstock coal-field, though not coming strictly within the limits of New Eed 

 Sandstone inquiry (the water being chiefly derived from the red marls above it 

 or the Coal-measures), is of interest, as showing the water-bearing properties 

 of these strata. i 



At Twerten Coal-pit, Twerton, near Bath, 16,800 gallons of water arc ' 

 thrown out every 24 hours by a spring in the Lower Lias, at a depth of 

 72 feet from the surface; the water was found to contain 112*8 parts per y/ 

 100,000 of chloride of sodium, by Mr. Ekin, F.C.S., of Bath. 



At Braysdown CoUiery, 500 yards in depth, a constant volume of water is 

 met with, which Mr. Biggs found to contain 1008 grains of common salt per , 

 gallon, or 1440 grains per 100,000 : the water appears to be derived from j 

 the Coal-measures, and is very salt indeed. ; 



The wells in Bristol, Mr. Stoddart, F.G.S., reports to Mr. Moore are from 

 60 to 300 feet in depth, situated on heights of from 10 to 200 feet above the 

 sea-level ; but the water is derived either from the red marls or the Coal- 

 measures lying beneath ; and some of the weUs are reached by tidal water. 



On the Steering of Screio- Steamers. By Prof. Osborne Reynolds. 



[A communication ordered by the General Committee to be printed in extensoJ] 



Theee does not appear, as far as my observation goes, to be any particular 

 difficulty in steering screw-steamers so long as they are going ahead under 

 steam, but rather the other way ; they then seem to be better to steer than 

 almost any other class of ships. Great difficulty often occurs, however, when 

 they are stopping, starting, or otherwise manoeuvring. Their vagaries arc 

 then so numerous as to give the idea that there is a certain degree of capri- 

 ciousness and uncertainty about their behaviour. This is, of course, mere 

 fancy ; and did we but know them, it is certain that there are laws 

 which these steamers follow under aU circumstances. In the hope of 

 arriving at these laws, I have been investigating this subject now for twelve 

 years as opportnnity offered ; and I had come, as I thought, to some leadino- 

 facts, when the failure of the ' Bessemer ' to enter Calais Harbour on the 8th 

 of May last seemed to establish them. 



It will be remembered that the ship entered between the piers at a speed 

 of 12 or 1-3 knots, the tide running strong right across the mouth of the 



