720 
PROCEEDINGS OF SECTION G. 
export aspect of Australian agriculture. I offer here some of the 
observations made with substances affected by lowering the tempera- 
ture to 32°, 
Fish radiates its heat more rapidly than meat ; meat more 
rapidly than fruit. Fruits contract by freezing, and different fruits 
are affected differently. Thus well-grown, matured apples contract, 
but thaw out again without injury to the quality of the fruit. 
Grapes rupture at 32°, aud seem to be injured by temperature lower 
than 45°. Oranges seem less affected than any other fruit by freez- 
ing ; ripe pineapples shrink, and are injured, while the unripe fruit is 
not so affected ; ripe bananas are injured, while the unripe seem to be 
helped towards ripening. 
Sugar-cane is not' injured by freezing when cut and maintained in 
the frozen state, but thawing sets up rapid fermentation. Cabbage 
becomes tender by freezing, and is generally improved. Passion-fruit 
shrinks and thaws out uninjured. Potatoes and turnips shrink and 
are injured by freezing, while carrots become sweeter by freezing. 
Eggs expand, and numbers burst at 32°. Maize is uninjured 
at 32°, and weevils are killed. The foregoing are results of 
observations that may be helpful in the study of cause and effect in 
treating material for shipment. Much has yet to be discovered, as it 
seems to me, concerning the effects of cooling, chilling, aud freezing 
upon the laws of crystallisation, condensation, and evaporation. As 
an instance, I find marked differences in fruits containing malic, 
tartaric, and citric acids. Possibly other substances, such as meat, 
fowl, fish, &c., may be affected by their leading chemical contents. I 
think it will be found that substances having the smallest natural 
proportions of water in combination will be affected least in the 
changes inherent to cooling and thawing. The latter process develops 
its most seri ms effects upon both meat and fruit that is soft in com- 
parison with what is more mature and solid. In this respect it is 
found that food tells upon animal substances, and even upon eggs. 
Soft, watery fruits carry badly. Instances may be cited of fish frozen 
in such masses that they could not he separated without injury on 
thawing ; also tongues, kidneys, &c., of sheep and cattle when frozen 
in masses. Thus matter containing heavy proportions of water gives 
best results when chilled or frozen singly. 
Brief though this outline is, immense possibilities seem to me to 
he associated with it, as results show. That facilities for cooling, 
chilling, and freezing will be amongst the greatest helps for extending 
our agriculture seems very evident. By this means grain may be 
stored in absolute safety as against the serious losses now inflicted by 
insects. 
Pigs may be killed and converted into sides and hams at any time 
of the year, when the meat can be cooled down to 40° before curing. 
Poultry, rabbits, hares, Ac., may be treated in somewhat similar 
manner. 
Cream can be cooled and carried to the central factories where 
uniformity in butter- making for export is possible. 
The whole subject is replete with such possibilities as may call out 
the best energies of the many able minds interested in the proceedings 
of this congress, and may tend towards the best interests of the 
country. 
