Ji8 Styrian Steel.-— Etajlic Strings. 



VIII. 



U/efu/ N(r;LCJ i-rfleiling various OhjcBs.— Styrian Steel — Elaflic Strings f:r Mijicil Iiijru- 

 tiunlj and other Purposes — IFhals luithout Cogs. 



J- ^ I. Styiijn Slci/. 



OOME time ngo I was favoured witli a vifit from Mr. P^amondini, an Italian gentleman 

 on his travels. He aflured me that the Styrian ftecl is made very well in Hungary, and can 

 be obtained from any iron originally fmeltcd with charcoal, and not with coke. He fays 

 that the fccret of the procefs conGfts in the management upon the hearth of the blaft or 

 refining furnace. If the iron be ftirred about while in fufion, it will afford bar h'on ; but 

 if the fcoria be fimply raked off as It rifcs, and the metal be left for a due time undifturbed 

 in fufion, and tl'.en taken to the hammer, it proves to be ftcel. He affirms, that tlie iron 

 made with coke will not cement into ilecl, but forms a flag. Perhaps this may arifefrom a 

 redundancy of plumbago. 



a. Elajlic Strings for Mujtcal Injiruments and other Purpofes. 



THE elaflic firing known by the name of c.itgut, and very ufeful for making the bands of 

 lathes, when its diameter is large, or the firings of mufical inRruments, when fmall, pofTefics 

 peculiar properties which are well known. As it is compofed of animal fibre, it is fubjefl to 

 putrefy by accidental moiflure, and on this account the flrength of fuch as appears to be per- 

 fc£l is very uncertain. 1 underffaml that mufical firings of catgut are not made in this coun- 

 try. An intelligent friend of mine made an experiment many years ago with filk to form this 

 lafl article. He wound the fingle thread or fibre of the filkworm, without twilling, till the 

 mafs of fibres formed a body equal to his wifh. He fmeared this mafs with white of egg, 

 which he rendered immediately confillent by pnfhng it through heated oil. The firing was 

 exquiCtely true, or uniform in its thicknefs. When tried upon an indrument, the tone was 

 not fatisfaclory to an accuflomed ear : the performer faid it was tubby, a word which I fup- 

 pofe has reference to the found emitted by a tub, and will, as I imagine, convey a correal 

 though perhaps uiuiefinable notion to a mufician. Mufical firings produce a found more 

 grave the greater their diameter or their length, and the lefs their tenfion. It is required 

 that this found fhould not only be intenfe and perfcft, but alfo that it (liould endure for 

 a certain fliort time without confiderable diminution. The maximum of thefc qualities, 

 ■when the length is limited, is aimed at by regulating the diameter and the tenfion. If the 

 diameter be too great, the found will not lafl ; if too little, it will be deficient in inlenfity. 

 There is an artifice by which the permanence of a grave found from a given length of 

 fifing is fecurcd, without requiring the tenfion to be much diminifhed. It confifls in adding 

 to the weight of the llrLng, without adding to its flrength or elaflic force. For this purpofe 

 a flender wire is wrapped round the firing, which with this load gives a very dlUcrcnt and 

 more lalling tone than a fimplc firing of the fame length. I believe it is admitted that the 

 tor.eofthefe firings is Icfs brilliant or clear, and I fuppofe the firings made by my friend 

 had the fame quality, the brittle indurated white of egg adding to the weight but not to the 

 clafticity. The caoutchouc or elaflic gum was at that time unknown. , I think it worth 

 trying with filk for mufical firings, and flill more in the fabrication of flrong bands for lathe 

 vork, to be ufcd inllead of catgut. 4 



3. Wheels 



