Comparative Analysis.of the Gum Resins. B51 
whenrevaporated) to dryness left,a residue, which when) well 
washed still furnished another gramme, of; the same resini- 
form substance, which was held-in -solution by:means of 
the nitric acid. Lime-water in excess, when poured into 
the water which had .been;used fon washing the-substance 
in question, ‘separated from: itod*2 «gramme,of coxalate of 
lime mixed witha small. quantityyefmalate of limes >The 
supernatant liquor contaiaed,a bitter-yeHow, matter, 
§ 1V..1t follows from these experiments that smyrrh is 
composed for the ‘most. part of a gum different: fromiany 
awvith whichwe are acquainted,——the chief proper ues of which 
es : 
. To ,acquire cohesion by means of heat, ; sia we 
guickdd its solutions, which ‘renders-it, partly insoluble in 
water. 
2. To produce ammonia upon; distillationyand, azotic, gas 
aby. the atitrie;acid, which «makes, it, resemble. animal sub- 
Stauces,» MiP Ou cy Zo SOM IGHO TG 
3. To unite with the oxides of leads mercurysand tin, by 
ideconiposing the soliation of these: ‘metals. tus Fay 
Myrrh, besides the above, contains about 23,centiemes of 
its weight of a bitter: resineus.matter, very fusible, 
ANALYSIS QF FRANKINCENSE. 
§ I. Tam ata loss to know on what authority Linneus 
‘thought that frankincense was produced’ by the Juniperus 
thurifer a, which is-peculiar to Spainand Portugal, and not 
known in Africa or Arabia, from. whence the incense is 
naan tous. °M.’Adansony whochas seen the tree that 
‘furnishes it, thinks, on the contrary, that'it ought to consti- 
tute anew genus, and that it is idicociee oclandria: telr agynid. 
The Moors eall it sowkious IM. Lamarck thinks this tree 
very like the Amyris gileadensis of Linnzus. 
Frankincense, or olibanumy as/it is met with in com- 
“merce, is a subrtanee of :a: yellowish white; dr ry, brittle, 
slightly acrid and aromatic, in masses of various sizes, semi- 
transparent, and covered externallywith a white fatinaceous 
dust produced) bythe friction of the tears against. each 
other, 
‘§ 11. Frankincense melts with difficulty on the applica- 
‘tion of heat: if we set fire to it with a candle, it:continues 
to’ burn ty itself, and leaves.a white cinder. 
Twenty grammes distilled. with water furnished about-a 
- gramme of volatile oil of a light citrine colour, and having 
the sinell of citrons. 
The same quantity when distilled on an open ‘fire yields 
a very 
