Notes . 
60 T 
Germinations : — 
Mustard 
. 100 per cent. 
“ Bountiful ” Peas . 
. 100 
Vegetable marrow . 
96 „ 
Musk .... 
. Good. 
Wheat .... 
96 „ 
Barley .... 
. 100 „ / 
I forwarded the samples (which were small) to Professor Dewar, and 
suggested that they should be each divided into two portions, one for 
a control experiment under ordinary conditions, the other to be 
returned to me after being subjected to cooling. Owing to some 
misunderstanding, this was not done ; but, as will be seen in the 
result, the omission proved immaterial. The seeds, it should be 
stated, were simply air-dried : they were ordinary commercial samples, 
and no attempt was made to further desiccate them. 
I pointed out to Professor Dewar the advisability of exposing the 
seeds to extreme changes of temperature as gradually as possible, 
a precaution which Messrs. Brown and Escombe carefully observed h 
He promised ‘to consider what can be done to avoid any disaster 
from this cause/ 
On July 21 he wrote to me: — ‘In spite of the weather I have 
carried out my promise, and cooled some seeds in liquid hydrogen for 
half an hour. I had to seal them up in a glass tube, cool first in 
liquid air, and then transfer to the hydrogen. They have, therefore, 
been cooled to — 2 5o°C., or — 252° C., while being in a vacuum 
(seeing the air left had no appreciable tension). The seeds, in other 
words, have been transferred to a condition resembling that of moving 
through space. Another set of the seeds have been cooled only in 
liquid air for comparison/ 
On July 22 he added, on returning the seeds: — ‘ There can be no 
doubt about the seeds being cooled, as they were in the hydrogen 
for more than an hour. In fact I used nearly 600 c.c. of liquid 
hydrogen/ 
The seeds came to me in the small packets of tinfoil in which they 
had been placed in the tube. On opening these it was observed that 
the seeds were as fresh and bright as before being subjected to the 
treatment. There was not the slightest discoloration observable 
1 Loc. cit., p. 1 61. 
