58 ANNUAL OF SCIENTIFIC DISCOVERY. 



in the puddling process, and, secondly, in the heating of the 

 puddled steel masses. In furnaces of ordinary construction a 

 constant deterioration of the puddled steel must necessarily take 

 place from the free oxj 7 gen present in the furnace ; but in the 

 Siemens' furnace the gases may be so regulated that a neutral 

 flame is produced, and, consequently, the steel mass is heated 

 without deterioration. 



I will not now enter into the question of economy of fuel, as 

 this has been often discussed at meetings of mechanical engi- 

 neers ; nor will it be necessary to enlarge upon the great advan- 

 tage, especially in large towns, of the absence of smoke, which 

 has been hitherto thought a necessary nuisance in all branches of 

 the iron manufacture. 



2d. The second improvement which I would wish to mention 

 is improved facilities for handling and moving these large masses 

 of iron when heated as above described, which is effected by hy- 

 draulic cranes and machinery of sufficient power to move these 

 large masses almost instantaneously either from the furnace to 

 the hammer, or vice versa, to raise and lower the load, or to in- 

 crease or decrease the distance of the load from the centre of the 

 crane. 



The truth of the old adage, of striking when the iron is hot, 

 will prevent any necessity of dwelling upon the advantage of 

 rapidity of movement in dealing with large heated masses of iron. 

 After the pieces of iron have been heated in the manner de- 

 scribed, and when the machinery shown has brought the forging 

 to the hammer, it is necessary that the instrument should be of 

 the most approved description to cope with the material under 

 operation in the best and quickest manner, and with the greatest 

 possible comfort to the workman employed at the work desig- 

 nated. Hammers that are described as suspended are employed ; 

 they are carried upon w rough t-iron girders, of 20 feet span, 

 which gives the hammer-man such room for his operation, and 

 such freedom from any obstacle to his work, as have seldom, if 

 ever, been accorded before, and so much room to the rear is re- 

 served that shafts 50 feet or GO feet long could readily be made 

 without any inconvenience. Abstract of a paper read by Lieut.- 

 Colonel Clay, of the Birkenhead Forge, before the British Association. 



CORROSION OF IRON GAS AND WATER MAINS. 



In an editorial on this subject the " Gaslight Journal" remarks 

 that the deposits which form in the interior of iron water mains 

 cause serious annoyance and loss to many of our water compa- 

 nies. To so great a degree does this evil extend, that strenuous 

 efforts are being made to substitute some other material for iron, 

 which shall possess all its valuable qualities, and at the same 

 time be free from liability to corrosion, and consequent obstruc- 

 tion. The appearance of this internal deposit is very singular 

 and assumes various modifications. Sometimes the corrosion is 

 of a uniform thickness, and appears to attack the surface of the 

 iron evenly, while at others the whole diameter of the pipe is 



