A large number of local resident' responded to the invitation of the Dirveturs of the National Govern rent Central Ming to visit the new institution in' Chapei yesterday jernoon, among the guests being Loy Chang, chief of the Public Bonds Department of the Ministry of Finance, and Mr, Jian" Chen, general manager of the Central Bank of China, Visitors—were shown round the Mint and all ex-Pressed thole astonishment at the regress which had been made since Mz. 'T. V. Soong was appointed Minister of Finanes, The Central Mint is situated at the north end of Gordon Road, on the Chapei bank of Soochow Creek. A wooden bridge costing about Tls. 29,090 was specially: "constructed: over the creek to facilitate access.
The Mint grounds measure about 88 mow of land, being surrounded by a 12-ft, boundary wall. Ther ces; a main Unrough a settling chamber wh staggered with brick baffle walls. Any particle of silver being carried away in the draught is caused to strike the baffle walls and fall to the ground by its own weight. Periodicalls," thousands of dollars are saved by removing the checker plates and by cleaning the settling chamber in-order to recover silver, particles.
Adjoining the melting room is the storeroom for crucibles and other; melting room equipment. Next to this is the sweep reducer room. Here the discarded crucibles are crushed in a jaw crusher, pulverized to an impalpable powder all mill, then dried in a centrifugal drier, im' order that the silver oon-tent absorbed in the pores of the crucibles may be recovered. This, room is next to the melting room, where the air compressors. supply Jand circulate air to the various jas entrance facing south and a rear entrance, facing west. The serouncds fare well Laid out with spacious laws and cement concrete roadways lined il we trees. In the centre there is 48 beautiful fountain. the main entranes, the Admit vation Building presents an imnig structure, being three storeys height, with' two two-storeyed wings, and built entirely Forced concrete. Were it not for tite sight of the smoke stack and the water tank tower in the rear, there would be little "idea that, Aiveetly behind the building, is. the industrial section of the largest and awrist up-to-date mint in the world.
Entering the building, one finds con the right hand side the offices of the Director and Vice-Director, the general affairs office and the waiting room. On the left, there ix the ceffice of the Technical Mint Expert. and offices for the superintendents fof the various departments, The seuy room adjoins these offices and it is completely equipped respect with "chemical apparatus ard supplies, mute-furnaces and scales. feature of this room ix thy nm -amount of Hight permitted to enter through a skylight above. ani the steel windows, this Tight aiding the rkmen in their weighin# operas us. Going upstairs, one turns 49 the left to find more attices and A spacious room for Directors' meetings. On the vight is the accounting department, in mo! enecious amees. "The third Moor wed as the sta living quarters.
Coming to the minting plant, this Keeti nested directly sith the vent of the administration Uuildinge, The bullion comes in ans asses through continuous chain of hour the slightest motion or tue, emerai he other side of the building labed coins. 'Trucks convey'
m bare to the make room, where the correct proportions ised to make up the silver The melting room, with sts. twa lone rows of gas fired furnaces, where the melting ix done. The woulds ave attacked to ball bearins, lables which run on tracks a furnace furnace for pouring purposes. The routed ingots are placed on racks:
special cooling: tubs, Brat in plain water then in a tio per cent, solu: tion of sulphuric acid' to being hack the silver lustre. If necessary, the rough edges of the ingots are ott. shearing machines, and, for Sing. sriooth, four copper-tined vise tables are provided, The silver filings fall through a hole ino a copper ined drawer. Before sending the ingots to be weighed in the ingot 1 room anil stored in the each ingot is identified stamped number.
detail that can possibly towards economy has been provided for, every. piece of waste cloth or paper is humed in a sitoep. reducer and' the "liver particles are yoenvered from the ashes and every drop of liquid from the water cool ing tubs and from the hurriis! tubs is drained to a special settling tank, from which the silver is recovered. On the floors and around the furnaces cast iron checker plate gratings are laid, Silver particles falling to the ground fall the checker plate holes and stay there and are not carried away by. the workmen's shoes. Before entering the chimney, the burned furnace gases are made to pass The ingots are weighed in the ingot weighing room and then kept a huge reinforced vault, There are three of these voulis altogether, tone being attached to the make-up room for the storage of bullion, ther being the ingot vault and a third being for finished coin. "Each Yault has six fect of reinforced eon-crete floors with 18-inch reinforced concrete walls and ceilings. Steel shelves carry the stored silver, eleetrio radiators are provided to dispel moisture and electric fans to. Vide good air circulation. The doors to these voulis, each 1 tons, are lof solid steel and fitted with time and double combination locks, Far outside communication, in ease one is accidently locked inside after the locks are. set, telephones are installed in each vault.
'The rolling room is where the next process of minting' is carried "There "are. two 14" x. 14" breakdown mills and eight 10
8 smaller mills for rolling down v the ingots strips. Micrometer adjusters attached to the tool ste rolls on each mill enable the strips to e exactly to the Fequited thick: nesses of the various denominations of cums. At the end of the rolling room there are six automatic strip feed punching presses where. the in blanks are punched out of the strips at the rate of 120 per minute. These punching presses also per of cutting chines, for a cutting device ix attached whereby the punched strips are automatically: out into eonvenicent Jengths for remelting.
The mext process takes place in the leaning and. annealing room, where the coin blanks are annealed in three rotary annealing furnaces, following which they are washed in automatic washing machines and then dried in centrifugal driers. The rotary annealing furnaces each have a thermostat for automatically controlling the temperature through control of the gas supply, The annealed coins are dumped into copper collauders and burnished with a week solution of sulphuric acid contained in leadclined " tubs neath the furnaces. An electric trolley hoist running overhead on an eyebeam conveys the copper—cole anders full of annealed blanks.
Jautomatie machines. Plain water, mixed with steam to bring i suitable temperature, is used. The machines are rotated about a verti= cal axis. with the coin blanks in-ide being agitated in the water. Tt may be mentioned that, except for the machine lod shop, which has a belt drive, each machine in the mint has its own motor drive. These motors total 130 and range from hip. on the automatic weighing machines to as high as 75 hep. on the breakdown rolling milly. The motors on the washing machines ave different from other motors in that they have special graphite earings. An oil bearing would be practical due to the fact that the attical axis of the motor—shaft would cause the oil to leak out, The centrifugal driers consist rotating perforating baskets, where-the wet coin blanks are' placed, the water extracted through the perforations and by drying from ait heated by passing through a steam With the blanks in an annealed condition and before having them feoined, the edges are raised in six upsetting machines, the purpose hheing to protect the too rapid wear-
Text read from the printed page and cleaned; old type leaves the occasional error.