24,8 Mr. Donovan on the nature and combinations 
colouring matter present) afforded me no sorbic acid. The 
fruits that contain the sorbic and malic acids together are 
apples, plums, berries of the sorbus, barberries, and sloes. Of 
these, the berries of the sorbus contain the greatest quantity 
of sorbic acid, unripe apples less, ripe apples and sloes still 
less, barberries very little, and plums least of all. The green 
berries of the sorbus, (perhaps,) those of the sambucus, and 
the plant sempervivum tectorum, contain no other than the 
malic; and agreeing with the foregoing statements, rasp- 
berries and gooseberries, as they contain citric and malic acids, 
contain no sorbic whatever. 
Observations on the malic acid. 
In 1785, during an examination of different fruits and ber- 
ries, Scheele discovered that gooseberries, beside lemon acid, 
contained one of a peculiar nature : this he afterwards found 
to exist in apples, without, as he thought, a sensible admixture 
of any other. On this account he gave it the name of apple 
acid, or malic acid. 
He also ascertained, that by the action of nitrous acid on 
sugar, a substance is produced, which shows no traces of 
nitric acid, yet unites and forms a soluble salt with lime, “ it 
therefore is not the oxalic acid.” By some other experi- 
ments he found that an acid is produced “ which does not 
differ in the least from the properties of the apple acid, and 
is accordingly the same.” 
This acid he detected in a great variety of vegetable juices. 
Since that period, Vauquelin has extended the catalogue, 
but of all other plants, it is most abundantly contained in the 
Sempervivum Tectorum. 
Scheele's process for obtaining malic acid is as follows. 
