258 SoientifiG Proceedings, Royal Dublin Society. 



XXIV.— ON A NEW ANALYSIS OF THE LUC AN SITLPHUR 

 SPA, BY J. EMERSON REYNOLDS, m.d., f.r.s., Professor op 

 Chemistry, University of Dublin. 



[Read March 20th, 1882.] 



I HAVE the pleasure to lay before the Society the results of a new 

 investigation of the once celebrated Sulphur Spa at Lucan, from 

 which it will appear that we have in the neighbourhood of Dublin 

 a mineral spring of considerable therapeutic value. 



The examination of the water was undertaken at the request of 

 tlie excellent medical officer of the district, Dr. Levinge of Lucan, 

 and, after some preliminary work, I visited the spa on the 10th 

 of February, 1882, when I made the necessary observations at 

 the source of the supply, and collected the samples that I after- 

 wards analysed in the Trinity College Laboratory. 



The water is obtained from a small iron pump, which latter 

 is quite close to the bank of the River Liffey and within the 

 demesne of Colonel Vesey, d.l. The learned Dr. John Rutty, 

 in his remarkable book,* published in 1772, states that the spring 

 was discovered in 1758, apparently by "Agmondisham Vesey, 

 Esq., and a little to the N.W. of a chalybeate spring in the 

 neighbourhood, formerly in some repute, but now neglected." 



More than a century since the well was " seven feet long, two 

 feet broad and -fifteen inches deep, and yields a large supply of 

 water, containing 82 gallons, and when emptied fills again in an 

 liour. The soil about is sandy and limestone." This well is now 

 covered in and some care taken to secure it from surface drain- 

 age, the water being lifted by a small pump as already stated. 



The spring still afibrds a good supply, and doubtless is derived 

 from the limestone shales found by the Geological Survey in the 

 immediate neighbourhood. 



The water as it issued after continued pumping had a strong 

 smell of sulphuretted hydrogen, and was slightly opalescent, as 

 are most other sulphur waters. Its colour, as observed through 

 a column of 250 centimeters, was greenish gray, indicating a minute 



* "An Essay towards a Natural History of the County Dublin, accommodated to the 

 noble designs of the Dublin Society " (now Eoyal Dublin Society). 



