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POPULAR SCIENCE REVIEW. 
the liquid, as soon as it "becomes clear again, an alcoholic solution of sugar 
of lead is added until another precipitate is formed, consisting of insoluble 
dextrin, sugar, &c. Sulphuretted hydrogen is added next, and the filtered 
liquid is boiled down. The acidulous residue is shaken up with ether and 
left to settle, when the ether containing the picrotoxin is drawn off. Picro- 
toxin is a strong tetanic poison, producing vertigo, convulsions, and death. 
It dissolves in strong sulphuric acid, forming a saffron-coloured solution. 
With sulphuric acid and potassic bichromate it assumes a red-brown, and, on 
h eating, a dark brown colour. Another test for picrotoxin is given in its 
action on cupric oxide, which it reduces from alkaline solutions, and when 
boiled with dilute acids takes up water, forming a substance which also 
reduces cupric oxide. 
The Effect of lodate of Potassium on Animals. — In a recently published 
paper, read before the Royal Academy of Belgium, Dr. Meslen, the author, 
gave the record of some experiments upon dogs, to which this salt was given 
along with their food. He concludes from his experiments that iodate of 
potassium is a violent poison ; but this paper is only a preliminary notice, 
it being the author’s intention to publish an exhaustive account of his ex- 
periments, and of the effects of this salt on the blood and internal organs of 
the animals experimented with. 
Lardaceous Disease . — At the retiring meeting of the Pathological Society 
for the present session, the report of the committee on Lardaceous disease 
was produced. This is the name recommended for adoption in the case 
that has received other names also. An increase of cholesterine and of 
chloride of sodium is said to be present, while the affected organs are de- 
ficient in potash. It was long ago pointed out by Dr. Dickenson that de- 
ficiency of alkali was probably dependent on its removal from the blood by 
profuse suppuration, after which the disease is most frequently met with. 
A Gift to Owen's College , Manchester . — Miss Brackenbury, of Manchester, 
has signified her intention, according to the 11 Society of Arts Journal,” to 
give 10,000/. for the establishment of a medical school in connection with 
the College, being 5,000/. for the erection of suitable buildings, and 5,000/. 
by way of endowment for the support of the department. It is suggested 
that, as the father of Miss Brackenbury was in the medical profession, it 
would be a graceful recognition for the governors to endow a Brackenbury 
professor. 
A New Theory of Nervous Action. — This, which was put forward some time 
since by Dr. Robert MDonnel, and escaped our notice, we now call attention 
to, for it is very remarkable, and worthy of serious consideration. The paper 
was read before the Royal Irish Academy. The theory is thus stated by the 
author : — u I conceive that the various peripheral expansions of sensitive 
nerves take up undulations or vibrations, and couvert them into waves capable 
of being propagated along nervous tissue (neuricity, as it has been named). 
Thus, the same nerve tubule may be able to transmit along it vibrations 
differing in character, and hence giving rise to different sensations ; and, 
consequently, the same nerve tubule may, in its normal condition, transmit 
the wave which produces the idea of simple contact, or that which produces 
the idea of heat — or, again, the same nerve tubles in the optic nerve which 
propagate the undulations of red may also propagate, in normal vision 
