137 
voiisti'uclion, and the expansion of tlie Iron cTani[)s and 
vvedg'es, that it is being taken down, pursuant to notice from 
the city surveyor.* 
A Paper, communicated by Dr. Smith, was read by its 
Author, Dr. Roberts, Physician to the Royal Infirmary, 
“ On the Effect of Food on the Reaction of the Urine.” 
It has been the universal belief, until recently, that the 
reaction of the human urine is, in health, unfailingly acid, 
and that a neutral or alkaline condition of it was either a sign 
of disease or the consequence of partaking of subacid fruits, 
the vegetable salts of which became chano-ed in the blood and 
appeared in the urine as alkaline carbonates. 
In IS'lb, Dr. B. Jones called this belief in question, and 
announced that after ordinary food of any kind, whether 
animal, vegetable, or mixed, the acidity of the urine in an 
hour or two became depressed, and frequently even changed to 
neutrality or alkalinity ; returning, however, again to its natural 
degree after the lapse of one or tvvo hours. In the “ Philosophi- 
cal Transactions” for 1849, Dr. .Tones brought forward a 
large number of experiments in suj)port of this view. 
Later experiments have failed to confirm the observations 
of Dr. Jones. Drs. Vogel and Bencke in Germany, and 
Dr. Sellers in Edinburgh, did not succeed in tracing any 
constant and direct relation between the digestion of food and 
the reaction of the urine. 
The experiments detailed in this paper were undertaken 
with a view of throwing additional light on this disj)ute. 
To that end the urine of a man 28 years of ago, weighing 
144lbs, in lobust health, living in most favourable hygienic 
condition, was examined by hourly observations on 38 days. 
* After gdmling and polishing the iron rust, it presented a black iridescent sur- 
face of almost metallic brilliancy, and similar, in appearance, to Elba ore. Tt was 
capable of being made into a magnet of considerable power and retentivencss.— 
j. r. j. 
