70 
and ammonium chloride in sealed tubes, whereby 
a mixture of chlorides in nearly theoretical 
amount is obtained. This is distilled from the 
open tube and afterwards submitted to careful 
fractional distillation in vacuo. The unique 
feature of the series is found in the fact that any 
member can be converted into the rubber-like 
polymer by heating, and that the latter, on dis- 
tilling at a higher temperature, breaks down 
quantitatively into a mixture of all the lower 
members ; it is, therefore, possible ultimately to 
convert any member completely into any other 
by heating and, distilling alone. The lower 
members, up to and including (PNCI.), are well 
characterized, finely crystallized bodies, while 
(PNCI,); is liquid. Their stability diminishes 
with increasing molecular weight, (PNCI.); be- 
ing unattached by boiling alkalies, while the 
rubber-like polymer is destroyed by boiling 
water. The formation of PNCl, and (PNCI,), 
could not be detected. The chloronitrides con- 
stitute the first extended series of inorganic 
polymers interconvertible by simple and direct 
means. 
Dr. Fireman gave an extended résumé of the 
work of Duclaux and others showing that the 
lactic acid producing bacteria are not so im- 
portant in the production of butter flavors as 
are the peptonizing bacteria. 
Drs. de Schweinitz and Dorset stated that in 
studying the products of the growth of the tuber- 
culosis bacilli in artificial media, it was noted 
that the reaction of the cultures usually becomes 
acid, and as Prudden and Hodenpyl had suc- 
ceeded in producing tuberculous nodules with- 
out necrosis by the intravenous injection of 
dead bacilli, it seemed as though it should be 
possible to isolate from cultures of tuberculosis 
bacilli an acid substance, which is responsible 
for the necrosis of tissue that always takes 
place in this disease. After many fruitless at- 
tempts they succeeded in isolating from artificial 
cultures a crystalline acid substance having a 
melting point of 161° to 164° C. which was 
soluble in ether, alcohol and water, and crys- 
tallized in needle-like prisms. The solution of 
this substance was optically inactive and did 
not give the biuret action. The preliminary 
analysis of this substance gave a formula, 
like that of teraconic acid and the other 
SCIENCE. 
[N. S. Von. VI. No. 132. 
properties correspond closely with this acid. 
Its identity if such has not yet been proved. 
When injected subeutaneously into guinea 
pigs it causes a slight inflammation and lo- 
ealized necrosis, and injected directly into 
the liver tissue by means of a hypodermic 
syringe it produces characteristic necrosis. 
The substance causes a reduction of temper- 
ature in tuberculous animals, and it seems 
probable that we have here the material which 
is responsible for the necrosis in tubercular in- 
fection. 
Dr. Wiley and Mr. Krug showed that vari- 
ous methods depending on the polarization of 
the starch or its inversion products, as well as 
others based on direct weighing of the starch, 
were too inaccurate to commend themselves to 
the analyst. The only accurate methods depend 
on the eventual inversion of the starch into dex- 
trose, which is then estimated by Allihn’s 
method. Experiments in the preparation of the 
Nitro-naphthalenes showed that they can not 
be prepared from c-naphthalene sulphonic acid, 
but that the best yield is obtained with mix- 
tures of nitric and sulphuric acids. The best 
results were obtained with 30° B. nitric acid, 
using about three times as much acid as 
naphthalene. The amount of sulphuric acid, 
used varies with the nitration degree desired, 
varying from 4: 1 (nitric: sulphuric) for low 
melting products to 3:2 for the higher deriya- 
tions. 
Dr. Cameron cited some of his own experi- 
ments to show that, although it is possible in 
the case of some heavy metals to replace 
chlorine by sulphur by merely boiling the latter 
with a solution of the chloride, it is impossible 
to obtain such a reaction with alkaline, or alka- 
line earth chlorides eyen upon heating in sealed 
tubes at a high temperature. 
Mr. Tassin gave a short description of a new 
mineral, but reserves the details for special 
publication. 
VY. K. CHESNUT. 
Secretary. 
TORREY BOTANICAL CLUB, MAY 26, 1897. 
THE President, Hon. Addison Brown, pre- 
sided. The evening was devoted to a lecture 
by Mrs. Elizabeth G. Britton, entitled ‘The 
