SCIENTIFIC SUMMAET. 667 
relief was instantaneous and permanent, and the coating fell off in the course 
of one or two days. 
The Origin of Dwarfism^ a subject of the highest interest to the teratolo- 
gist, has been lately discussed in the Academy by M. Dareste. In his 
memoir M, Dareste attributes the cause of dwarfism to an accelerated develop- 
ment. His experiments were conducted upon hen-eggs which were under- 
going incubation. Of a number of eggs which were being hatched, some 
underwent their completion more rapidly than others, and these M. Dareste 
examined. On the 3rd of June, at two o’clock, he opened the shell of an 
egg which had been placed for incubation at ten o’clock on the morning of 
the 2nd. The embryo had been some time dead, so that the entire duration 
of its life could not have extended over more than from twenty-four to twenty- 
six hours. * Nevertheless it had attained a condition of development which 
under ordinary circumstances must have taken sixty hours to arrive at. The 
left side of the head was bent upon the vitellus, though the rest of the 
body had its ventral surface applied to the vitelline mass. This precocious 
embryo was exceedingly small, and its measurements were far below those of 
ordinary embryos which have attained a similar degree of development. M. 
Dareste, employing the expressions of M. Isidore Geoffrey Saint-Hilaire, 
shows that embryonic phenomena are of two kinds : first, the formation of 
definite organs from a structureless mass — this is development ; and, second, 
the increase of their organs — growth. If the latter process be in excess of 
power, a giant is produced ; but if the former, a dwarf is the result. 
The use of Iodide of Potassium in Mercurial Palsy has been illustrated in 
a case which was described in a late number of the Comptes Pendus. The 
symptoms and treatment of the disease were stated in a sealed packet, which 
was forwarded to the French Academy in 1843, and which was recently 
opened and read, at the desire of its authors, MM. Melsens and Natalis 
Gudlot. The patient, who had complained for years of pains which had 
resisted all forms of treatment employed to remove them, was put under the 
influence of iodide of potassium, given, according to M. Melsens’ formula, in 
the proportion of 4 grammes of the salt to 125 of water. The medicine was 
each day repeated in the same dose for a period of twelve days, at the end of 
which time the pains completely disappeared, and the patient was discharged 
well. The deductions, drawn with some reserve by the savants, and which we 
suppose they have since corroborated, are as follows : — (1.) In the case of 
tradespeople who work with'mercury, this metal is liable to become deposited 
in the tissues. (2.) Mercury may be removed in the condition of a double 
salt by the action of iodide of potassium. 
The Therapeutical Action of Mineral Waters. — It cannot be denied that 
miueral waters possess therapeutical powers of some importance. We do not 
mean when they are taken into the system through the ordinary channel, but 
simply by their contact with the surface of the body. The fact of the 
existence of so many watering-places, where baths of mineral water are 
employed, is of itself alone an argument in support of this opinion. 
But though the remedial property of mineral waters be established, their 
modus operandi is as yet hardly ascertained, and is at present the subject of a 
very animated controversy in the French Academy, between M. Scoutetten 
and certain other savants. The later researches of M. Scoutettn have been 
