WRITINGS OF JAMES SMITHSON. 101 



paratus, represented above, I could not perceive a trace of 

 it. A more accurate observation of its fusion has shown 

 me that it does not, as generally supposed, form the cauli- 

 flower. It appears to do so only where so large a mass is 

 exposed to the fire that but points of its surface are fused in 

 succession. If a very minute bit is employed, it is clearly 

 seen to puff up like borax, stilbite, &c.; and then, like them, 

 become less fusible; from the separation, doubtless, of a 

 vapourized element on which its greater fusibility had 

 depended. The smallest particle of fluor spar shows no 

 fiuch inflation. 



We see here three several cases of intumescence in the 

 fire: one where a gas is absorbed; one where a gas, or 

 vapour, is disengaged ; one where the two effects are con- 

 comitant. 



There may be persons who, measuring the importance of 

 the subject by the magnitude of the objects, will cast a 

 supercilious look on this discussion; but the particle and 

 the planet are subject to the same laws ; and what is learned 

 upon the one will be known of the other. 



AN EXAMINATION OF SOME EGYPTIAN 

 COLOURS. 



From Thomson's Annals of Philosophy, Vol. XXIII, New Series, Vol. 

 VII, 1824, p. 115. 



January 2, 1824. 



Sir: More than commonly incurious must he be who 

 would not find delight in stemming the stream of ages: 

 returning to times long past, and beholding the then state 

 of things and men. 



In the arts of an ancient people much may be seen con- 

 cerning them : the progress they had made in knowledge of 

 various kinds ; their habits; their ideas on many subjects. 



