382 



[Other analyses were given, which we regret our inability 

 to insert.] 



That in a large proportion of cases, my reports are sub- 

 stantially unfavourable, though in such guarded language 

 as — " not the worst I have known," — better is desirable 

 if it can be procured," is not to be imputed to my being 

 hypercritical ; but to the fact before adverted to, that chem- 

 ical analysis is not often resorted to at the period when 

 it would be most useful, at the formation of the line, when 

 the quality of the water might enter as one element into 

 the fixing on the exact site of a station, but that it is when 

 the water is found unfit, that an analysis is thought of. 



In regard to a remedy for crust, I believe the best is to 

 select such water as, from its obvious softness, or from analy- 

 sis, is shown to be of a good kind. Where no very good 

 water is to be found near the spot which on other iiccounts 

 must be selected for a railway station, or a steam engine, 

 frequent and early drawing off and blowing out" will 

 remove much of the separated earthy matter before it has 

 time to attach itself firmly to the boiler. 



I have repeatedly heard that potatoes, or other similar 

 substances, are in actual use, in the boilers of some station- 

 ary engines ; they must act by enveloping the particles of 

 earthy matter in a slimy coating, which lessens the tendency 

 to adhere to each other, or to the metal, not by diminishing 

 the quantity. They could not be applied, I think, in loco- 

 motives, without inducing the other defect of priming. One 

 patent enumerates among the methods which it claims, the 

 having some part or parts of the boiler, away from the 

 hottest portion of the furnace, at a lower level than the 

 rest, and so situated that the eddies of the water, in its 

 course from the hotter to the cooler portion and back, should 

 leave much of the deposit in these recesses, where, the in- 

 ventor imagines, I apprehend correctly, they would adhere 

 less firmly than to the strongly heated plates. 



