116 Mr. Wuldle's Investigations connected [No. 2. 



appear to have attracted the attention that was clue to them. I shall 

 also draw my own conclusions from my results, stating at the same time 

 with what amount of confidence they are made. 



Inorganic constituents. 



In the original communication, on account of an unforeseen and 

 unexpected source of error which vitiated some of the results and 

 therefore rendered the series incomplete, only a general view of the 

 relative proportions of alkaline and earthly salts at the different 

 seasons, taken from the tables in Dr. Macnamara's Report, was given. 

 It may he of interest to state the nature of the source of error, then 

 only hinted at. It occurred in the case of the waters of December 

 and February, greater part of which had been kept in green glass 

 stoppered bottles till the month of April, which, on analysis, gave 

 results so peculiar as to excite surprise. The same peculiarities were 

 found in some of the analyses of the river water of August, in even 

 a more marked degree. After not a little perplexity and trouble, 

 it was ascertained that this arose from the action of the water on the 

 glass, dissolving the glass in such proportion as altogether to vitiate 

 the result as regards the proper constituents of the water ; it having 

 been ascertained that the silica, the alkalies, and the lime of the glass 

 were all added in notable proportion to the constituents of the water. 

 It was the very large proportion of the silica obtained that first drew 

 attention to the subject. Not being specially connected with the 

 object of this paper, it is not necessary to notice it more particularly 

 than to observe that there can be little doubt, but that it is due in 

 great part to the increased activity given to the solvent action of the 

 water by the high temperature of the climate, though indeed it occur- 

 red to a sufficiently decided degree even during the coolest months. 

 There is probably little doubt that this circumstance has in many cases 

 introduced error into water analyses unobserved. The analyses, in 

 the present case so vitiated, were rejected and new ones instituted as 

 the season gave opportunity. 



For the purpose of comparison, the most complete plan would be, 

 to ascertain the amount of each basic and acid constituent and state 

 these in detail. A very general, or rather the general plan hitherto 

 followed by chemists, has been to allot the acids and bases to each 



