}2 Observations on Naphthaline. 
By agitation with an aqueous solution of potash, or of am- 
monia, it communicates a slight wheyishness to those fluids ; but 
soon separates from and floats on the top of them. 
Absorbs several times its volume of ammoniacal gas, without 
any sensible change. 
Absorbs also several times its volume of muriatic acid gas; 
becoming, in consequence, opaque and thick. 
Forms a uniform white soapy curd with a solution of acetate 
of lead, by the invervention of an aqueous solution of potash or 
of ammonia; but, if simply mixed with the metallic solution, it 
soon separates without any sensible change. 
Properties of the white concrete Substance. 
Taste, pungent and aromatic. 
It is particularly characterized by its odour, which is faintly 
aromatic, and not unlike that of the narcissus and some other 
fragrant flowers, This odour is readily diffused through the 
surrounding atmosphere to the distance of several feet, and ob- 
stinately adheres for along time to any substance to which it has 
been communicated. 
When in its purest state, and reduced to powder, it is ex- 
ceedingly smooth and slightly unctuous to the touch; is perfectly 
white, and of a silvery lustre. 
Sp. gr. rather greater than that of water. 
It does not very readily evaporate at the common atmospheri- 
cal temperature: for, a comparison being made between this 
substance and camphor, in the quantity of half a grain of each 
in a very minute state of division, it was found that the camphor 
had entirely disappeared at the end of 18 hours, while the sub- 
Pg tit in question had not disappeared entirely at the end of four 
ays. 
A quantity of it being exposed to heat, in a glass vessel, soon 
melted; but did not begin to boil till the temperature had reached 
410° of Fahrenheit: the heat being then withdrawn, it remained 
liquid till cooled down to 180; at which point the lowest por- 
tion was seen suddenly to congeal; the remaining portion con- 
gealed gradually; and when the whole had become solid, its 
temperature was 170°. The structure of the congealed mass 
was distinctly crystalline, and the crystalline laminz were slightly 
flexible. 
It is not very readily inflamed; but when inflamed it burns 
rapidly, and emits an unusually copious and dense smoke, which 
soon breaks into distinct particles that fall down in every di- 
rection, } 
Does not affect the colour either of litmus or of turmeric. 
Insoluble in cold water ; and very sparingly soluble in boiling 
water, 
