122 
volatilizes very readily and is rapidly extracted 
from the finely pulverized substance by sodium 
thiosulfate solution. The sulfur left after the 
extraction of the iodin is readily soluble in 
carbon bisulfid. It would seem that in the 
‘iodized sulfur’ the iodin is merely dissolved in 
the sulfur. The ‘sulfur iodid’ is prepared by 
adding pulverized iodin to sulfur heated to 200°. 
While cooling, the mass is poured into cold 
water and then powdered. The iodin cannot 
be dissolved out by thiosulfate solution and 
seems to be in chemical combination. The 
color of the sulfur iodid is yellowish red ; that 
of the iodized sulfur brownish black. Both 
substances, especially the latter, are energetic 
therapeutic agents. 
THE question of the form in which iodin 
occurs in the sea water has received a new 
answer from Armand Gautier in the Comptes 
Rendus. It is questionable how much experi- 
mental evidence can be deduced to show the 
presence of sodium iodid or calcium iodate, 
though both of them have been proposed. 
Gautier claims that all the iodin in sea water is 
in the form of organic compounds. About one- 
fifth is combined in alge and spores, and the re- 
mainder in the form of soluble organic com- 
pounds ; the latter are in part derived from the 
decomposed algze, and are in turn assimilated 
by other algze. It would be an interesting thing 
to have this question settled once for all, but 
the problem is one of great difficulty. 
THERE is also presented in the Comptes Ren- 
dus a study by M. De Forcrand of the chemical 
function of water compared with that of hydro- 
gen sulfid. From the heats of formation of the 
oxids of sodium the author concludes that the 
two hydrogen atoms in a molecule of water 
are distinctly different in function, and hence 
that water possesses an asymmetrical formula 
which he would represent by H—OH. In 
hydrogen sulfid, on the other hand, he considers 
the hydrogen atoms of equal value, and it con- 
sequently possesses a symmetrical formula 
H—S—H. 
ACCORDING to the Pharmaceutische Central- 
Halle Varino has succeeded in preparing a col- 
loidal form of bismuth. The very diluted solu- 
tion of bismuth tartrate in potassium tartrate is 
SCIENCE. 
IN. S: Vox. X- No: 239: 
treated with a solution of stannous chlorid in 
caustic potash. A clear brown fluid results, 
from which very little bismuth precipitates, and 
which acts toward the electrical current in a 
similar manner to colloidal gold. 
ACCORDING to the Chemical News, one of the 
the most interesting exhibits at the recent 
Royal Society Conversazione was the series of 
experiments by Mr. W. A. Shenstone and Mr. 
W. T. Evans, showing the manufacture of 
tubes of rock crystal in the oxyhydrogen blow- 
pipe flame. Tubes of one centimeter in diam- 
eter, composed of rock crystal, can now be 
made of considerable length at the rate of 
about three’ centimeters an hour. This is of 
great practical as well as theoretic interest. 
do 10, Jeb, 
RECENT PROGRESS IN THE EXAMINATION 
OF FOODS AND DRUGS. 
PLANT PRINCIPLES. 
As the result of some investigations on the car- 
bohydrates in bulbs, tubers, ete., L. du Sablon * 
gives the following information: The reserve 
materials in the tubers of potato, rhizomes 
of Arum and Iris and the corms of Colchicium 
and Ranunculus consist almost entirely of 
starch, with small quantities of dextrin and 
sugar. In the tubers of Ophrys and the bulbs 
of Lolium, Tulipa and Hyacinthus the reserve is 
made up of starch and dextrin. In the corm 
of Ficaria starch, dextrin and non-reducing 
sugars are present. In the tubers of Dahlia 
inulin and levulin are found ; whereas in the 
tubers of the artichokes, besides the inulin 
and levulin, non-reducing sugars are present. 
Chiefly reducing and non-reducing sugars are 
to be found in the bulbs of Alliwm and Aspho- 
delus. The experiments of du Sablon seem to 
show that the starch is transformed into dex- 
trin, then into non-reducing sugars and finally 
into reducing sugars. 
Tnulin has been found by H. Fischer} to 
occur in most of the tribes and a large number 
of genera of the N. O. Composit. It is also 
found in the Campanulacez, Lobeliaceze, Good- 
eniace, Stylidaceze, ete. He assigns to it the 
formula 333 CyHy)O; or Cy99sH3330Or665- 
* Bonniers Rev. Gén. de Bot., 1898 ; Ibid., p. 295. 
{+ Cohn’s Beitr. Biol. Pflanz., 1899, p. 53. 
