LOCOMOTIVE ENGINES.

729

antimony, two parts; copper, one part and a half. Other materials to beobtained of the manufacture to be hereinafter specified, unless the consentof the Company ’s locomotive Superintendent in writing be first obtained toan alteration.

Boiler. —Barrel, dome, fire-box casing, and smoke-box tube plate, and allangle irons, rivets, and stays to be made of Lowmoor, Bowling, Taylor’s,or Cooper’s (best Yorkshire ) iron. Barrel to be telescopic, and made intwo plates, the circumferential seams to be single rivetted, and the longi-tudinal seams to be butt-jointed, with inside and outside Strips, doublerivetted. Tube plate to be attached to barrel by a ring of angle iron,bored, faced, turned on edges, and shrunk on, and zigzag rivetted to both.The dome to be in one plate welded at the seam, and flanged at the bottomto fit barrel, to which it is to be double rivetted; a strengthening liner plateto be placed inside the barrel round the opening for the dome. The topto have an angle-iron ring rivetted to it, and to be fitted with a strongwrought-iron cover. The cover and angle iron must be accurately facedso as to make a perfectly steam-tight joint. Fire-box shell to be made asshown, the sides and top in one plate, the front or throat plate flanged for-ward and single rivetted to the barrel, and the back plate to the sides andtop as shown. Angle irons for carrying the sling stays to be rivetted to thetop in the position shown. The manhole to be of wrought iron, flangedtop and bottom, and single rivetted to the casing, the top flange to beaccurately faced to receive the safety valves. The boiler to be stayed bysix longitudinal stays screwed into the back plate of the casing, and passingthrough the smoke-box tube plate, with nut and washer on either side, theback plate to be strengthened where the stays pass through by a liner platerivetted to it on the inside. The longitudinal stays to be supported in themiddle of their length in the manner shown. The fire-hole to be circular,the ring of the section shown to be Yorkshire iron, rivetted to the casingand fire-box plates, flush outside casing. The foundation ring to be York­ shire iron, the corners of the form shown, carefully rivetted, so as tobe thoroughly tight. Twenty-one brass taper mud plugs for washing outto be placed in the positions shown on the drawings . 1

Dimensions.

ft. in.

Length of barrel ... ... ... ... ... ... ... 10 2

Diameter ,, outside at fire-box end ... ... ... ... 4 3

Thickness of barrel ... ... ... ... ... ... ... o ofa

,, tube plate ... ... .. ... . o o %

1 These specifications are only supplied to selected firms of engine builders, who areiuvited to tender (upon the specification), and the drawings can be seen at the chief officeof the Locomotive Engineer of the Railway Company . After a tender has been accepted,a complete set of detail drawings are supplied by the Company, and these have to becarefullv worked to.