In organic chemistry, we have learnt to derive from compounds containing only carbon and hydrogen, i.e. from the hydrocarbons, all other types of combinations, such as alcohols, aldehydes, ketones, acids, etc.

In bitter almond oil, like in a great number of other substances that previously had been counted among the 'aromatic compounds' on behalf of their strong smell, a derivative of benzene is present. The special properties of benzene and its derivatives are caused by the typical arrangement of their carbon atoms.

Organic compounds exist in which a hydrogen atom, joined to the carbon, acquires acid properties as a result of the proximity of certain functional groupings.

As soon as chemists have a definite conception of the internal structure of the molecule of an organic compound, they are able to tackle the task of producing these substances by artificial methods, i.e. by synthesis, as we call it.

As soon as we can wrest from Nature the secret of the internal structure of the compounds produced by her, chemical science can then even surpass Nature by producing compounds as variations of the natural ones, which the living cell is unable to construct.

Most of the oils which are valued as scents are mixtures of substances; only the combined effect of these leads to the known result.