PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 545. 



circumstances, are known to communicate a highly deleterious quality to 

 their contents, yet in the open waters, from which the large cities, already 

 named, have been supplied through such pipes, no practical evil, of a gen- 

 eral nature, is known to this Board to have resulted from their employ- 

 ment. 



"4. That when individuals may prefer not to employ, for purposes of 

 food, water which has passed through leaden pipes, they may introduce it 

 into a lower reservoir through pipes of iron, or other safe material, and 

 conduct it from thence for other purposes, to different parts of the house, 

 through lead tubes, properly guarded by stop-cocks, valves, or other 

 mechanism;" and thus leave the commissioners in much the same doubt 

 as before ; the whole report is very non-committal, but evidently leaning 

 toward the use of lead, without the boldness to take the responsibility 

 upon themselves of advising its use. 



We now take up the chemical testimony, commencing with Dr. Hayes, of 

 Lowell, at present of Boston, who uses the following language : 



"It has been supposed, from imperfect experiments, that waters con- 

 taining certain small portions of salts, do not act on lead. Some years 

 have passed since the opinion, favoring such a conclusion, was published. 

 The lapse of that time has permitted the accumulation of facts and obser- 

 vations, which, placing the fallacy of such an opinion beyond doubt, have 

 established the conclusion, that, all natural waters act on leo.d chemically, 

 under the varying states of atmospheric changes. Lead, as a material for 

 pipes, cannot be safely used for conducting water, which is to be used for 

 domestic purposes. The water, from the source of supply, for the city of 

 Boston, has, in a high degree, the power of destroying lead pipes ; and 

 even salts, in a crystalized form, have been observed to result from this 

 action." And afterwards remarks upon the kinds of lead pipe in use : 



" Two kinds of lead pipe are found in commerce ; the one made by the 

 'patent' pro'cess, in which heated lead is forced through dies, has its sur- 

 faces imperfectly coated with tin. The other, cold drawn from thick tube, 

 in general use, better resists corrosion." Thus confirming your committee 

 in the beli<3f already formed, that the manner of tinning lead pipe up to 

 that time, was not satisfactory. Dr. Hayes also makes the following 

 important statement: "The quantity of metal dissolved and suspended, 

 was several times obtained. Metallic lead, in a globule as large as an 

 ordinary pin head, was obtained from one quart of Cochituate water, after 

 twenty-four hours exposure, as a mean result." 



Dr. Jackson, of Boston, and Prof. Silliman, of New Haven, also confirm 

 Drs. Webster and Haj'es' opi-nion, as well as Dr. Dana, of Lowell. 



Up to this point, all the opinions of the chemists employed by the com- 

 missioners to investigate the subject, had been decidedl}' adverse to the 

 use of lead pipe. In the meantime. Prof. Horsford had been engaged in a 

 series of experiments upon this subject, and your committee wish to call 

 your attention to this report, as it was the result of a long continued com- 

 parison of various waters from New York, Philadelphia, Albany, Troy, 

 Cambridge, and Boston. Upon the commencement of his investigations, 



[Am. Inst.] J* 



