COLLKCTIONS IN KCONOMIC Gi:<)l.<>(;Y AND Ml/l'A l-Ll'iaJ Y. l!»7 



every on*-, ;iiitl takes tlic place orc<»|»|»(i in iiiaii\ casrs wht'ii- ii answers 

 just as well aiul eosts considerably less. 



In the manufacture of brass ji e.ertain amount of scrap brass is tirst 

 nu'lted in a crucible, in order to <,nve a tlui«l bath on the bottom of the 

 crucible, ami into this is put Jie proper amount, (h'pendinj,^ upon the 

 «;rade of brass desiieil, of tjopper. wliicli is melted. The contents (»f the 

 crucible must now be broujfht to just the rij^ht tem[)eratur6; if it is too 

 cold it is heated ; if too hot, ami this is ^ienerally the case, it is cooled or 

 tempered by addin>; strips of brass. If it is too cold the zinc will not 

 mix proi)erly with the eoi)i)er; if it is too hot the zinc wdl be volatilized 

 and the contents o[' the crucible boil over. 



Bein^' at the right temi)erature the zinc is added. Since zinc oxidizes 

 very easily it is customary to add an excess, about 5 per cent., for loss, 

 but with care it is possible to reduce the loss to 1 percent. Sometimes 

 small amounts of other metals, especially lead, are added to {^ive special 

 «p>alities to the brass. When the zinc is thoroughly incorporated with 

 the coi)per the melting is finished and the brass is ready to be cast. 

 The form into which it is cast depends upon the use to which it is to be 



l)Ut. 



Great care is required in casting to secure good results. The cruci- 

 ble is first skimmed and then poured. If poured too fast air will be 

 entangled with the metal aiul the casting will be unsound from blow 

 holes ; if poured too slow dross will catch on the sides of the mold and 

 make bad spots in the casting. The crucibles hold 100 to 130 pounds, 

 and, since the work is very exhausting, the melters work only to 8 

 hours a day, producing tive to six heats. The average product of good 

 brass is about 75 per cent, of the materials charged. 



The manufacture and utilization of brass as practiced at the works of 

 the Ansonia Brass and Oop[»er Company, Ansonia, New Haven C()unty, 

 Connecticut, is illustrated by a full collection taken by Mr. llenry 

 Cooi)er, 1884. 



(I) Copper, used iu the iiiannfacturo of brass. (54393.) 



(•J) Spelter or iiietallic ziue, ustnl in the manufacture of brass. (Tyi'MS.) 



(3) l'i<; lead, used in the manufacture of lirass. (54394.) 



(4) Scrap brass, ol»tained from tht^ ashes of the castin<rshop by washing. (54395.) 



(5) Oxide of zinc, ol)tained as a ctHoresceni-e in working up the refuse of the casfinjj 

 shop on letting the metal stand for a long time iu the crucible in the furnace. 

 (5439li. ) 



(t)) IJrass crucible, in use for tifty rouiuls of molting. (54:{i>H.) 



(7 ) Coniniuu or high lirass, kIiowh the brass as cast into a bar one and one-qnarter 

 inches thick, and tin- bar reduced to one<[uarter incbthick by rolling. Composition, 

 two parts copjuT toiuie part /.inc. (5438<). ) 



(H) Brass, that can be workt-d hot or <ol<l, .sliowiiig tlie oar as cast, am' tlu> re<luc- 

 tion of the same l»ar by rolling ; the cast rod '2 iuches s(|uare is 1»rokcn down t<> 

 Mi'ven-eighths of an inch round, hot, and fmishod cold. Composition, three parts cop- 

 per to two parts zinc. (5437r). ) 



(9) Brass, that can be worked hot or cidd; a test piece hammered out hot. Com- 

 position, three parts copper to t'Ao jiarts /.inc. (.511150.) 



(10) Clock bra.s.s, eml»ossed. (54390.) 



