WRITINQS OP JAMES SMITHSON. 91 



scale of operating ; and thus render the sacrifice which must 

 be made as small as it is possible. 



M. de Saussure's* ingenious contrivance for subjecting 

 the most minute portions of matters to fire, by fixing them 

 on a splinter of sappare, appeared to fulfil the conditions of 

 this problem, and to have accomplished all that could be 

 desired. It has, hovi^ever, been scarcely at all employed, 

 owing to the oxcessivo difficulty in general of making the 

 particles adhere ; and in consoquenco the almost unpossessed 

 degree of patience required for, and time consumed by, 

 nearly interminable failures. 



That such should be the case could not but be a subject 

 of much regret, for besides economy of matter, of time, of 

 labour, and the great beauty of deriving knowledge from so 

 diminutive a source, and attaining important results with 

 such feeble agents; reduction of volume became, in this in- 

 stance, productive of increase of power, and thence, of an 

 extension of the series of qualities by which substances are 

 characterised. 



A slight alteration which I have made in M.. de Saus- 

 sure's process has removed the objection to it. To water, 

 saliva, gum water, which he employed, the last of which is 

 not sensibly superior to the former, I have substituted a 

 mixture of water and refractory clay. 



Small triangles, or slender strips, of baked clay may be 

 used in lieu of sappare, which is not at all times to be pro- 

 cured ; or a little of the moist clay may be taken up on the 

 end of a platina, or other wire, and the object to be tried 

 touched with it. This way may be applied to pieces of the 

 ordinary size, and supersede the use of the platina tongs. 



But a proceeding which I have only recently adopted ap- 

 pears to deserve the preference. Almost the least quantity 

 of clay and water is put on the very end of a platina wire, 

 filed flat there. With this, the particle of mineral lying on 

 the table can be touched in any part chosen ; for a moment 



* Journal de Physique, par Rozier, tome 45. 



