Chenistry and Physics. 143 
of baric hydrate ; but whether the chlordibromacrylic acid thus 
obtained is identical or isomeric with the other remains to be 
determined. The study of the acids thus obtained by Dr. Ma- 
bery is still in progress. 
Dr. L. P. Kinnicurr and Mr. G. M. Parmer have studied the 
f phenyltribrompropionic acid. This acid was obtained by the 
addition of dry bromine to the 6 bromcinnamic acid (melting 
point 120°C.) The substance is soluble in alcohol, ether and chlo- 
totorm. By recrystallization from chloroform it can be easily 
purified, and when so obtained melts at 151° C.) It is decomposed 
by boiling water, giving the a bromcinnamic acid (melting point 
132°C.) ; together with a-new acid, very soluble in water and 
melting at-184° C., which is beyond doubt a phenyldibromlacti 
acid, and an oil which boils with slight decomposition: at 253°— 
255° C. This oil is a dibromstyrol which when exposed to bro- 
mine vapor forms an addition-product. This addition-product, 
itself a very thick oil, is probably a tetrabromstyrol, and we ex- 
pect that the study of the products formed when this last body 
18 treated with boiling water, or with alkalies, will show the con- 
stitution of the dibromstyrol, and by inference that of the mono- 
romeinnamic acid whose melting point is 120° C. and which is 
commonly called the £ acid, although the position of the bromine 
In the molecule has never been satisfactorily determined. 
n the course of his work Dr, Kinnicutt has devised a method of 
lately shown that carbonic oxide can be obtained by ss ere 
a _nearly pure, containing less than one per cen 
dioxide, The magnesite used was that from Eubca in Greece, 
which is imported here for making artificial stone, but any form 
of anhydrous magnesic carbonate would serve as well. 
Mr. Joun N. Nur t ; ler t 
difection of Dr. Kinnicutt, some experiments on the determination 
of nitrous acid by potassic permanganate 
ry 
accurate results could be obtained by the following modification 
of the process. To a solution of a nitrite in water, two or three 
drops of dilute sulphuric acid are added, then immediately an 
excess of potassic permanganate, the volume of the standard solu- 
tion used being accurately measured. Next ten to fifteen cubic 
