170 
POPULAE SCIENCE EEVIEW. 
to the same thing in the end. Even doubtfully pure water 
may be drunk with impunity if previously boiled, or distilled, or 
carefully filtered. The filter, however, should not permit 
organic particles much larger than the xoW 
meter to pass through it, if we would be perfectly certain as to 
the absence of the eggs of the Tcenia ecJdnococcus. 
It is a matter of no small moment to notice that, as in the 
case of Tcenia solium, one human individual acting the part of 
host in any given neighbourhood, may endanger the lives 
of several of his fellow-creatures ; so also mav one canine 
host,^^ or bearer of the Tcenia echinococcus, serve us a similar 
turn. It was partly from my knowledge of this circumstance 
that I was induced to suggest a preventive rule at the Cam- 
bridge meeting of the British Association in 1862, which rule 
I may here be permitted to repeat. It is this : “ All entozoa 
not preserved for scientific investigation or experiment should 
be destroyed by fire, and under no circumstances whatever 
should they be thrown aside as harmless refuse."’^ This pro- 
position is not merely given as a hint to commencing in- 
vestigators and pathologists ; but, rather, to unscientific meat- 
inspectors, butchers, fieshers, knackers, and their associates, 
who, from benevolent motives, are in the habit of flinging 
doubtful portions to dogs which frequent their neighbour- 
hood. In this way the tapeworms are frequently reared, and 
our lives are consequently placed in jeopard}’. Echinococcus- 
cysts are well known to butchers, and I have even see these 
and other entozoa brought to table. 
Beee, Poeter, &c. — All I need say in regard to these 
fermented drinks is that, entozoologically speaking, they are 
perfectly harmless. Even though impure waters were employed, 
the boiling of the worts would alone be sufficient to destroy 
any number of parasite eggs which might previously exist. 
In non-fermented drinks, however, such as ginger-beer, 
lemonade, soda-water, and the like, we cannot be absolutely 
certain of avoiding parasite eggs and larvae. It all depends 
upon the source whence the manufacturer procures his supply 
of water. In most cases it is obvious he will have obtained 
the cleanliest within his reach ; and therefore we may con- 
clude that, generally speaking, there is little or no danger to 
be apprehended on this score. In regard to wines, the same 
remarks are, to a certain extent, apphcable. Any considerable 
amount of alcohol added to water is certainly sufficient to 
destroy the vitality of parasite eggs or their larv£e ; but I very 
much doubt if the amount of sphht ordinarily developed in our 
home-made Enghsh wines is sufficient to effect this purpose. 
Manifestly, it is advisable that only the purest water should be 
employed in the preparation of all these drinks; for then only can 
we be said to be absolutely certain of avoiding parasite infection. 
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