132 



weeks ; not more than a quarter of a grain of lead was then obtained, 

 and the conclusion is drawn that after a very considerable period the 

 solution of the lead would probably cease. 



Further experiments also proved that a mixture of Eivington water 

 with Green Lane, in the proportion of two of the former to one of the 

 later, acted decidedly upon the lead. When mixed in equal proportion 

 a slight but perceptible effect was produced ; but in the proportion of 

 two parts of well water to one of Eivington, no action took place. 



It appeared important practically to ascertain what action the water 

 would have upon the incrustation already formed by the well water 

 upon the interior of cisterns in the town. Experiments on the subject 

 show that while the tendency of the water is to disintegrate and detach 

 the coating, it does no*' dissolve lead thei'efrom even after a period of 

 long contact ; the coatirg already existing upon old cisterns will 

 therefore still prove some protection. 



It did not appear that any lead was dissolved by the mere passage of 

 water through leaden pi])es, and it was observed that no injury to the 

 public was likely to arise from the use of this water, provided that 

 leaden cisterns be well coated with good paint or a sviitable cement.* 



TWELFTH ORDINARY MEETING. 



Held at the Royal Institution, on the 20th April, 1857, 



De. IHNE, Vice-President, in the Chair. 



The following gentleman was elected an Ordinary Member : — 

 N. S. Glazebrook. 



Dr. Thomson exhibited an admirable miniature painting of the late 

 President, Joseph B. Yates, Esq.,F.S.A., being a coloured photograph, 

 by Mr. Foard. Its faithfulness, delicacy, and artistic beauty were 

 much admired. A photograph, by Mr. Keith, of the chaste and well- 

 cut tablet by Mr. J. P. Macbride, erected to his memory in the ancient 

 chapel, Toxteth Park, was also shewn by the Rev. Mr. RoBBERns, 

 who described the manner in which the artist had so successfully 

 introduced chromatic colouring into the marble sculpture. 



* A more detailed account of these and other experiments has been published in a 

 separate form, and may be obtuined from the authors, or through the secretary. 



