84- INSTRUMENT FOR MEASURING TENACITY. 



the scale, till the screw is turned the contrary way to bring 

 it back to the zero. Figs 5, 6, 7, &c. represent such parts 

 as may not perhaps be quite intelligible in the perspective 

 view of the instrument: namely the screw and nut, stand- 

 ards, &c, all of which, 1 hope, will be understood, without 

 a more diffuse description. 

 Applicable to The application of the smicrologometer to ascertain the 

 cords of any tenacity of metals being understood, it will be easy to con- 

 kind: ceive, that it may be readily employed in the same way, to 

 determine the strength of silk, cotton, or linen threads, &c, 

 affording thereby means of calculating with facility the force 

 any combination of them will sustain in cordage, cloth, &c. 

 and to stringed It will likewise be found a desideratum to those manu- 



lnstruments of f ac ^ urers of stringed musical instruments, who wish to ap- 

 mu»ic. . „ & . ...... r 



proximate to perfection on scientific principles. 



It being now determined by experiment, that the trans- 

 mission of clear and continuous sounds from piano fortes, 

 harps, &c, depends very much on the due proportion 

 of their component parts, and more particularly those 

 to which the wires or strings are immediately attached ; it 

 becomes in consequence necessary, that the exact tension, 

 *f strings producing different sounds should be known as 

 correctly as their lengths, in order, that such proportions 

 may be given as will exactly support the aggregate tension 

 without impeding the vibrations by unnecessary quantities, 

 of metal or wood. 



Mode of tp- To adapt the smicrologometer to this purpose, nothing 

 plication to r , „ ° i i . • I . , 



these. is necessary, but to affix a monochord scale with a movable 



bridge on the top of the piece of wood A A : when you have 

 an instrument that will determine at once the length and 

 tension of any string, or wire, to the highest degree of accu- 

 racy, that is capable of practical application. 

 Experiments Satisfied that every invention and discovery, having the 

 with the in- prospect of opening a shorter and less intricate avenue to 

 mised. truth, comes with a fair claim to approbation from all who 



are interested in the advancement of science; I shall not 

 hesitate to lay before the public, in some future paper, the 

 results of a number of experiments made to ascertain, more 

 correctly than has hitherto been done, the relative tenacity 

 of the different, metals, and their alloys: accompanied with 



such 



