Midland Agricultural and Dairy Institute . 117 
all of which had some direct bearing upon agricultural subjects 
and were illustrative of the several departments of instruction 
as carried out at Kingston. 
1. Assimilation of Free Atmospheric Nitrogen by Crops } — 
A series of experiments in pots containing boiled sand, photo- 
graphs of other pot cultures, and sample plants taken from 
field experiments showed the results obtained with the various 
new inoculating materials for leguminous crops. The results 
indicated that the German cultures supplied by Dr. Hiltner 
were well capable of producing nodules on plants grown in 
sand free from the nodule organisms of the plant under 
experiment, and most satisfactory results were also obtained 
with cultures made in the laboratories of the Institute by a 
new method : viz., by filtering crushed nodules through 
porous porcelain filters, which allowed the small form of the 
nodule organism to pass, but held back the impurities. 
The American cultures, on the other hand, did not produce 
such good results, and plants fertilised with them were often 
but little better than those which were obtained without 
nitrogen and without inoculation. 
Peas exhibited from one field trial showed very good 
results with the dressing of the nutrient solution containing 
the American culture ; but it was pointed out that the seed for 
the control plot had not been dressed with a manurial solution 
without the organisms, as should have been done to get a strict 
comparison. 
2. Dairy Bacteriology . — Cases were shown illustrating the 
effect produced by good and bad ventilation of cow byres on 
the number of bacteria in the air, and the effect of washed and 
sterilised pails on the germ contents of milk. A new organism 
was shown which produced a taint in milk containing copper. 
3. Potato Culture . — This section consisted of photographs 
and diagrams concerned with the life-history and growth 
of potatoes. Boxes of seed, tubers, and seedlings produced 
by hybridisation were shown. Some of the seedlings were 
shown in pots bearing a label upon which was written the 
parents from which the plants had been obtained by crossing. 
Jars of museum specimens illustrating the formation of tubers 
in the early life of the plant, and the ripening of the seed 
towards the end of the season, were included. Comparison 
of these furnished material for connecting the two methods of 
reproduction in potatoes. 
Some tubers were exhibited which bore evidence of a new 
potato disease, very conspicuous on tubers of the Evergood 
variety obtained from Lincolnshire. They were accompanied 
1 See also page 211 of this Volume. 
