PROGRESS OF MICROSCOPICAL SCIENCE. 
139 
only Jg of tlieir capacity was occupied ; the air admitted was passed 
through red-hot iron pipes filled with iron wires. There is a 
similarity between these two sets of experiments ; the flasks were not 
entirely in contact with the hot liquid. We see also, from the few 
words quoted from the description of Child’s experiments, that a 
sufficient space intervened between the red-hot tube and the bulb to 
allow of the heated air becoming cool before it entered the glass bulb; 
it cannot be said, therefore, that the entering air was so hot as to 
destroy whatever living thing might be attached to the glass. The 
precautions taken, then, were not sufficient to render the experiments 
trustworthy, more particularly in the case of Wyman’s work, because 
there he had an immensely large surface untouched by fluid, and 
naturally he obtained more results in favour of the view of evolution 
than any other experimenter. Bastian’s own experiments are open to 
the same objection ; in fact, it seems that much work has been 
rendered faulty by this neglect of bringing every part of the interior 
surface of the containing vessels in contact with the heated liquid. 
We have positive proof that such is the case when, as Bastian himself 
states, “ it has long been known that a boiled fluid extremely prone 
to change will not yield infusoria if the vessel in which it is contained 
is filled with the fluid the commercial method of preparing cooked 
meat depends upon this to a great extent. 
The Power of various Substances to destroy Protoplasmic and Fungus 
Life has been inquired into by Dr. F. Crace-Calvert, F.R.S., who has 
published a paper on the subject in the ‘ Broceedings of the Royal 
Society.’ His experiments consisted in adding to a solution' of 
albumen swarming with microscopic life, one-thousandth part of the 
following substances, and examining the result after one and sixteen 
days. The experiments were begun on the 20th Sept., 1871, the solutions 
being kept at a temperature of 15° — 18° C. In the standard solution 
the amount of life and putrescence increased during the whole of the 
time. The first class includes those substances which completely 
destroyed the locomotive power of the vibrios immediately, and com- 
pletely prevented their regaining it during the time the experiments 
were conducted : — Cresylic acid.. The second class contains those 
compounds which nearly destroyed the locomotive power of all the 
vibrios present when added, and afterwards only one or two could be 
seen swimming about in each field : — Carbolic acid, sulphate of quinine, 
chloride of zinc, and sulphuric acid. The third class are those which 
acted injuriously on the vibrios on their addition, leaving only a 
small number retaining the power of swimming, but which allowed 
the vibrios gradually to increase in number, the fluid, nevertheless, 
containing less life after sixteen days than the standard putrid 
albumen-solution Picric acid and sulpho-carbolate of zinc. The 
fourth class includes those substances which acted injuriously at first, 
but permitted the vibrios to regain their former locomotive power, so 
that the fluid after sixteen days contained as much vibrio-life as the 
standard putrid albumen : — Chloride of aluminium, sulphurous acid 
and prussic acid. The fifth class contains those compounds which 
acted injuriously at first, destroying the locomotive power of most of 
