1864. | Physiology. 753 
path examined pus presenting a greenish-blue colour. He found that 
the fluid lost its colour on being corked up in a close bottle, but re- 
assumed the blue colour on exposure to air. He supposed that this 
was due to the presence of a colourless material analogous to Indigo 
and the action of oxygen on it. He obtained crystals from the pus in 
six-sided plates, and aciculi of a deep-blue colour when sublimed. 
Other tests were employed which furnished evidence of the presence of 
Indigo Blue in the pus. 
Dr. John Davy, “On the Temperature of the Sexes.” Dr. Davy, 
from observations made in the Tropics and in England, supported the 
view that the temperature of the male is greater than that of the 
female. 
Dr. G. D. Gibb read a note, “On the Action of the Bromides of 
Lithium, Zine, and Lead.” The first of these was prepared with the 
view of treating gout and rheumatism ; in small doses it acts as a tonic, 
gentle stimulant, and sometimes as a diuretic. The Bromide of Zine 
relieved impaired nervous power, whilst the Salt of Lead acted as a 
soothing and cool local agent in some inflamed states of the mucous 
membrane. 
Dr. Hayden read a paper, “ On the Relative and Special Applica- 
tions of Fat and Sugar as Respiratory Food.” He believed that fat 
and sugar possessed different values as food; that they underwent 
different transformations, during which they subserved distinct pur- 
poses of the economy; that the period of their retention in the body 
is the same; that they are not mutually convertible; but that ulti- 
mately they pass out of the body under the common form of carbonic 
acid and water, and are jointly concerned in the production of animal 
heat. He considered that fat, being an assimilable substance, can 
under no circumstances be applied to the maintenance of animal heat 
before undergoing the twofold process of constructive and destructive 
assimilation, but that amylo-saccharine substances are immediately 
and directly passed off from the blood, and are never assimilated in 
the proper sense of the term. The general conclusions he had arrived 
at from his experiments were as follows :—The amount of fat deposited 
in the body is regulated by the absolute and relative quantity of olea- 
ginous and saccharine matter in the food taken ; both substances taken 
ina large quantity, cause excessive deposits of fat. If the fat taken be 
in defect, even though the sugar be in excess, no increase in the deposit 
of fat takes place, but rather a decrease, obviously in consequence of 
ordinary molecular absorption, to which the adipose, in common with 
other tissues, is subject, not being counterbalanced by assimilation. If 
the fat taken be in excess, whilst the sugar is insuflicient to meet the 
immediate wants of the respiratory function, still the deposit of fat 
may not undergo increase, but the contrary, apparently because a por- 
tion of that already deposited must undergo reabsorption into the blood 
forthe purpose of supplying heat. Fat is, therefore, as a heat-producing 
substance, only supplemental of sugar, which is the ordinary pabulum 
of respiration. Saliva, like gastric juice, is secreted in quantity strictly 
proportioned to the immediate wants of the system, and quite irrespec- 
