NOTES ON LEMON-JUICE AND ITS DECOMPOSITION. 207 
tative matter, especially that part of the mesocarp that forms what is com¬ 
monly called the white of the rind. 
The ingredient in the juice, which is the therapeutic agent, seems to be 
a matter of dispute among medical men. Those who advocate Dr. Garrod's 
views—that it resides in the potash—must have a homoeopathic idea of its 
value, and plenty of faith. 
The analyses of many specimens of ash show only grain of potash per 
ounce. Others, with Dr. Tanner, and I think with more reason, rely on the 
citric acid as the chief means for curing scurvy. 
The molecules of citric acid are very remarkable for their tendency to 
change, especially when sugar or gum is present. As remarked before with 
regard to lemon-juice, so a solution of crystallized citric acid cannot be eva¬ 
porated to dryness without decomposition, even with a very gentle heat. 
Like all seaport towns, a great many cases of scurvy are present in Bristol, 
and I have the authority of several of our leading physicians for saying that 
they find the crystallized citric acid as efficacious as lemon-juice (especially 
with fresh meat and vegetables) in curing that disease. 
But as this question is more in the sphere of the physician than the phar¬ 
maceutist, it had better be left in their hands for solution. 
Mr. H. S. Evans said, with reference to the alleged extensive adulteration of lemon- 
juice, that he knew there were at least two firms in Liverpool who imported this article 
direct from Messina. Upon its arrival this juice could not pass the inspectors unless 
having 7 per cent, citric acid and 5 per cent, alcohol. He had a good deal of experience 
in the examination of such imported juice, and had always found from 7 "5 to 9 per cent, 
of citric acid and 4 to 5 per cent, of alcohol. But there could be no doubt that great 
adulteration was practised, and the Act had done much good by putting a check upon 
this. With regard to the case in which citric acid was said to have been used for forti¬ 
fying weak lemon-juice, he (Mr. Evans; was disposed to query whether a scarcity of 
lemon-juice might not only justify such a procedure, but render it necessary. 
The President confessed to have been much struck by the facts brought forward by 
Mr. Stoddart to show that lemon-juice might contain no free citric acid. He considered 
that lemon-juice freshly squeezed was the only sort that should be used in pharmacy. 
The lemon-tree was a singular instance of a tree bearing fruit at all seasons of the year, 
its inflorescence proceeding simultaneously. 
Mr. Deane reported his own procedure to be the following :—He laid in a stock of 
lemons when plentiful in spring, squeezed the juice, heated it to 180° F., and bottled 
it whilst hot in small bottles, that were then tied over with bladder. In this way the 
juice kept good for many months. 
Mr. Schacht remarked upon the extreme interest of the question raised by the dis¬ 
appearance of the citric acid. What had become of this ? 
Mr. F. C. Clayton gave some interesting particulars derived from an extensive ac¬ 
quaintance with the commercial aspects of the question. He said that the Board of 
Trade allow lemon-juice having a specific gravity of 1-003, whilst pure juice should be 
1 -004. A change of practice had lately occurred as to the addition of spirit, for, as 
white rum (which was formerly used) caused the juice to turn to a dark greenish-yellow, 
it was now omitted. With reference to the kindred subject of lime-juice, he had usually 
found this to have a density of 1-0048, and to give 11 ounces of citric acid per gallon. 
The practice now obtained of importing lime-juice in a concentrated state, having a 
density of D024. To test the effect of heat, he had evaporated 20 ounces of lime-juice 
to 2 ounces, then re-diluted, and found the density not to have changed. 
Professor Attfield thought that the disappearance of citric acid in the manner sug¬ 
gested, namely, by conversion into glucose and other bodies, was to be regarded as one of 
the most important of Mr. Stoddart’s observations, and demanded further attention. 
Referring to the therapeutic question, he trusted that members of the medical profession 
would institute experiments to decide whether the citric acid was the efficient agent, or 
the salts of potassium. 
Mr. Groves said that the fruiterers recognized what they called “ sweet lemons.’ 
