32 ANNUAL OF SCIENTIFIC DISCOVERY. 



prepares the plant by cleaning it first with weak caustic alkali, and 

 then with dilute sulphuric acid, after which it is washed, and before it 

 is quite dry it may be pressed into sheets or any other form. It then 

 may be rendered very hard by steeping it in a hot solution of 

 alum, after which it is removed to a hot room where it is dried, and 

 retains its shape afterward. Reduced to powder it may also be 

 mixed with various substances, like india rubber, and moulded into a 

 great variety of articles. When it is bleached, by treating it first with 

 a- warm alkaline solution, and afterward with sulphurous acid gas, it 

 resembles ivory and may be used as a substitute for that material. 



MANUFACTURE OF STRINGS FOR MUSICAL INSTRUMENTS, 

 AND OTHER USES, OF GUT AND SINEW. 



The London Mechanics' Magazine publishes the following interest- 

 ing article on the above subject : 



A manufacture, of which comparatively little is known, is the pre- 

 paration of the substance usually termed catgut, though for the most 

 part made from the dried, twisted, peritoneal coverings of the intes- 

 tines of sheep. Catgut cord is used for a variety of purposes where 

 strength and tension are required, as for the strings of musical instru- 

 ments, for suspending clock-weights, bow-strings for hatters' use, and 

 for archers' bows. 



The manufacture of musical strings requires a great amount of care 

 and skill, both in the choice of materials and in the manufacturing 

 processes, in order to obtain strings combining the two qualities of re- 

 sistance to a given tension and sonority. Until the beginning of the 

 last century, Italy had the entire monopoly of this trade, and they 

 were imported under the names of harplings, catlings, lute-strings, 

 &c. ; but the trade is now carried out, with more or less success, in 

 every part of Europe. However, in the opinion of musicians, Naples 

 still maintains the reputation of making the best small violin strings, 

 because the Italian sheep, from their leanness, afford the most suitable 

 material ; it being a well ascertained fact, that the membranes of lean 

 animals are much tougher than those of high condition. The smallest 

 violin strings are formed by the union of three guts of a lamb (not 

 over one year old), spun together. 



The chief difficulty in this manufacture is in finding guts having 

 the qualities before mentioned, namely, to resist tension, and giving 

 also good vibrating sounds. It is far more easy to arrive at the proper 

 point in the making of harp, double-bass, and other musical strings, and 

 the manufacturer is not so much circumscribed in the choice of the 

 proper material. The tension upon the smallest string of the violin, 

 which is made of only three guts, is nearly double that on the second 

 string, formed by the reunion of six guts of the same size. 



In the preparation, the sheep's guts, well washed and scoured, are 

 steeped in a weak solution of carbonate of potash, and then scraped 

 by means of a reed cut into the shape of a knife. This operation is 

 repeated twice a day, and during three or four days, the guts being 

 every time put into a fresh solution of carbonate of potash, prepared 

 to the proper strength. In order to have good musical strings, it is 

 indispensable to avoid putrid fermentation ; and as soon as the gutg 



