BOILERS AND PIPES. 



237 



boilers, &c, care should be taken that it 

 be rain water, if possible, for all spring or 

 hard waters are impregnated with matter 

 which will soon form sediment or incrus- 

 tations in the boiler, and ultimately in 

 the pipes also ; which will not only im- 

 pede the operation of their working, but 

 be attended with dangerous consequences. 

 The incrustations which form on the bot- 

 toms of boilers prevent the water in them 

 from acting on the surface of the metal 

 while the fire is acting on the other side ; 

 consequently, the bottom is soon burnt 

 out, and the whole apparatus rendered 

 for a time entirely useless. These in- 

 crustations usually consist of carbonate 

 and sulphate of lime, together with sul- 

 phate of soda and magnesia, with other 

 salts, according to the nature of the 

 water used. 



A patent has recently been taken out 

 by Dr Babington of London, for prevent- 

 ing incrustation in boilers, by voltaic 

 agency. For iron boilers, he recommends 

 a plate of zinc, 16 oz. to the superficial 

 foot, to be attached at one of its edges by 

 solder to the interior of the boiler ; and 

 both sides of the plates being left exposed 

 to the action of the iron and water, the 

 voltaic agency thus excited is said to 

 have the desired effect. 



If, in first filling a new boiler, a pint of 

 tar be poured in, and the boiler then filled 

 up with the water, the thin film of tar 

 which floats on the surface attaches itself 

 to the metal. The lime deposits, adher- 

 ing to the tar instead of to the iron, fall 

 to the bottom, and can be cleaned out 

 by occasionally emptying the boiler. A 

 teacupful of tar thrown into the boiler 

 once a fortnight will in this way entirely 

 prevent calcareous incrustations. 



A compound of coal-tar, linseed water, 

 plumbago, or black lead and soap mixed 

 together, has a similar effect. 



To clean boilers of incrustations, Hood 

 recommends "a weak solution of muri- 

 atic acid (one part of acid by measure 

 to twenty or thirty parts of water.) 

 This," he says, " will reduce the concreted 

 sediment, and render it of easy extrac- 

 tion." One ounce of sal-ammoniac to every 

 ninety gallons of water, occasionally ap- 

 plied, is said to keep them clear of in- 

 crustations. And it has been asserted 

 that mahogany sawdust put into the 

 boiler will completely answer the same 



purpose ; but of this we have had no 

 practical proof. 



Br Ritterbandt's invention for pre- 

 venting crust in steam-boilers has been 

 highly spoken of. The principle on 

 which it is based is the chemical action 

 which the muriate of ammonia exerts 

 upon the carbonate of lime, the incrust- 

 ing material. Dr Ritterbandt discovered 

 that, by introducing muriate of ammonia 

 into a boiler containing water holding 

 lime in solution, the carbonate of lime, 

 instead of depositing when the carbonic 

 acid by which it was held in solution was 

 expelled at a high temperature, became 

 converted into muriate of lime — a sub- 

 stance eminently soluble— while the car- 

 bonate of ammonia, likewise formed by 

 the double decomposition, passed off with 

 the steam, so that the boiler could not 

 foul. The process is equally applicable 

 to fresh and salt water. The inventor 

 has proved, that when sea water is boiled, 

 the incrustation produced is not formed 

 of salt, but of calcareous matter — the salt 

 not depositing until the water has at- 

 tained a density far beyond that at which 

 the boilers of marine engines are worked. 

 The object of the frequent blowing off 

 which obtains in practice, is to prevent 

 the accumulation of the deposited calca- 

 reous matter. By preventing the forma- 

 tion of carbonate, by the addition of 

 muriate of ammonia, the necessity of 

 blowing off is, to a great extent, dispensed 

 with ; for while with the best-contrived 

 apparatus it is found impossible to con- 

 tinue working at a density above 20° 

 marine hydrometer, with the plan of Dr 

 Ritterbandt a density of 60° may be safely 

 employed. Three-fourths of the quantity 

 of water usually blown out is thus econo- 

 mised, and consequently that proportion 

 of the loss of fuel saved. The soundness 

 of Dr Ritterbandt's principle has stood 

 the test of time and experience. Twelve 

 months have elapsed since his discovery 

 was brought under the notice of the 

 public, and in that time its operation has 

 been tried in every variety of way with 

 eminent success — in large and small 

 steamboats, in stationary and locomotive 

 engines, working with water from all 

 localities — and in every instance has it 

 been found perfectly effective, not merely 

 in keeping the boilers, wherever it has 

 been applied, clear of deposit, but in dis- 



