963 
brittle, possessed a violet colour, and did not emit light in the dark: 
We started again from the same preparation; it was heated in a 
tube of not readily fusible glass in vacuo for twelve hours at 510°, 
so above the supposed transition point, and then it was suddenly 
cooled. Then half of the tube was heated in a bath at 200°, to 
condense the white phosphorus that had deposited from the vapour 
in the colder upper end of the tube. After careful cooling the tube 
was cut in the middle, and the glass spring (pressure indicator) was 
filled with the red phosphorus obtained in this way. Then the glass 
spring was evacuated by means of the pump and heated in an 
asbestus jacket at +150 for an hour to be sure that all the air 
was expelled, and then fused to at the bottom. The heating should 
not be carried up higher than 150°, because else, as appeared later, 
a great disturbance of the internal equilibrium takes place in conse- 
quence of the pumping off of the most volatile molecule kind from 
the phosphorus, which disturbance is only gradually prevented at 
higher temperature. 
That in this way we really succeeded in removing all the air from 
the glass spring appears from this that at the end of the determinations 
no appreciable zero point change of the glass spring could be 
demonstrated. 
The vapour tensions determined with this phosphorus were much 
too high, higher than before, and presented a close resemblance with 
that of the white phosphorus for the lower temperatures. It followed 
from this that the white phosphorus had not been sufficiently removed 
from the preparation, and that a subsequent treatment had to follow 
to remove it completely. 
In future the violet phosphorus was therefore extracted in a Sohxlet= 
apparatus with CS, for 6 hours, and then treated with ammonia to 
remove the possibly formed phosphoric acid. Then the preparation 
was washed with absolute ether, and dried in a vacuum exsiccator 
over P,O, '). 
Now three preparations were made, which were all subjected to 
the same after-treatment, which we shall designate by : 
Preparation N°. 2 made from preparation N°. 1 by heating it 
once more with 0.1 °/, Iodium at 375° for six days, and then sub: 
jecting it to the said after-treatment. 
Preparation No. 3 prepared from white phosphorus by first heating 
it without Iodium at 300° for some hours, and then once more 
\) In this after-treatment part of the pseudo-component soluble in the CS, will 
of course be ejected from the mass, which is in internal equilibrium. This, however, 
is of no importance, as this is restricted to the surface-layer only. 
64* 
