52 Section of the Strata [Jan. 



old ; and which is remarkably interesting in a physiological point of 

 view, as shewing the power of the retina to preserve its susceptibility 

 to light for twenty years, though not the only case recorded. There 

 was certainly in this case a great approximation to the phenomena 

 manifested in congenital blindness, but there was not that marked 

 ignorance in recognising objects at first sight, nor that palpable 

 want of correspondence between the touch and sight, but both existed 

 to some extent. It was also curious that he should become blind 

 after five years of the same disease with which his brother was born 

 blind. 



I recollect restoring a man, aged 35 years, who had been blind for 

 a period of twelve years from the venereal disease, causing closure of 

 the pupils. This man, after an operation for artificial pupil, recognis- 

 ed, of course, every thing perfectly the moment he was permitted to 

 look about him, and still enjoys a very tolerable share of vision at 

 Cawnpore. 



VI. — Memorandum of the progress of sinking a Well in the bunds of 

 Chandpur, near the foot of the Hills. By Mr. William Da we, Con- 

 ductor, Delhi Canal Department. 



In sinking wells through the soils, without and within the lower 

 range of hills, I have seen repeated failures owing to the usual mode 

 adopted in digging for the water, (i. e. with perpendicular sides;) and 

 as I was only about 400 yards from a branch of the Jumna, the level 

 of its water about 14 feet below the surface of the top of the pro- 

 posed well, I calculated upon finding water at 20 feet deep at the 

 utmost. I therefore commenced digging 42 feet diameter, contracting 

 as I sunk, and this admitted of leaving a couple of winding steps to 

 bring up the contents by basket loads, in preference to being drawn 

 up with a drag- rope, (which method could not well be adopted, the top 

 excavation being so wide.) At the depth of 24 feet I was appre- 

 hensive that the work would have been a failure, owing to the vast 

 accumulation of heavy boulders, from 4 to 10 maunds weight, which 

 I had no purchase to get up. This obstacle was got over by the 

 simple method of expending one for every step of the winding road- 

 way, always taking the precaution of letting the boulders sufficiently 

 into the bank to prevent the possibility of their falling down on the 

 work-people below. By this method down as deep as 37 feet the 

 boulders were expended as we came on them, and as the soil there 

 had a more favorable appearance for working, and there was a proba- 

 bility of soon getting water, and the space had become so contracted, 



