THYME.--All the different species of thyme, but more
particularly the lemon thyme, the _Thymus serpyllum_, as well as the
marjorams, origanum, &c., yield by distillation fragrant ottos, that are
extensively used by manufacturing perfumers for scenting soaps; though
well adapted for this purpose, they do not answer at all in any other
combinations. Both in grease and in spirit all these ottos impart an
herby smell (very naturally) rather than a flowery one, and, as a
consequence, they are not considered _recherché_.

When any of these herbs are dried and ground, they usefully enter into
the composition of sachet powders.

TONQUIN, or TONKA.--The seeds of the _Dipterix
odorata_ are the tonquin or _coumarouma_ beans of commerce. When fresh
they are exceedingly fragrant, having an intense odor of newly made hay.
The _Anthoxanthum odoratum_, or sweet-smelling vernal grass, to which
new hay owes its odor, probably yields identically the same fragrant
principle, and it is remarkable that both tonquin beans and vernal
grass, while actually growing, are nearly scentless, but become rapidly
aromatic when severed from the parent stock.

Chemically considered, tonquin beans are very interesting, containing,
when fresh, a fragrant volatile otto (to which their odor is
principally due), benzoic acid, a fat oil and a neutral
principal--_Coumarin_. In perfumery they are valuable, as, when ground,
they form with other bodies an excellent and permanent sachet, and by
infusion in spirit, the tincture or extract of tonquin enters into a
thousand of the compound essences; but on account of its great strength
it must be used with caution, otherwise people say your perfume is
"snuffy," owing to the predominance of the odor and its well-known use