ENTOZOA IN RELATION TO PUBLIC HEALTH, ETC. 355 
were most instructive, part of them being embodied in a 
brief paper published in the Lancet for May 13, 1865. 
Much of the information which I have thus acquired will 
never be utilised in any way. In this relation, therefore, I 
may be excused for remarking upon the good results likely 
to follow the delivery of short special courses of lectures on 
helminthology as part of the ordinary medical curriculum. 
The subject is eminently practical ; and at the Middlesex 
Hospital, I have found students who, though they thought 
it a nuisance to attend lectures on botany, have not failed to 
manifest great interest in my discourses on parasites in rela- 
tion to the diseases of mankind and animals. 
I see by the Times of December 12, 1870, that the Medical 
Officer of the Privy Council has commented very severely on 
the power of water companies in general, and of the Vaux- 
hall Company in particular. That criticism, of course, bears 
reference to the spread of diseases — such as fever, cholera, 
diarrhoea, and dysentery — in consequence of the ascertained 
presence of sewage impurities of drinking-water. From 
the strong language employed, one would almost be led to 
think that the responsible officers of these companies were 
divested of the commonest feelings of humanity. Of course, 
such cannot be the case. In all probability these gentlemen 
are by no means satisfied as to the “ proofs” of their power 
for evil ; or, in other words, they do not see the connection 
between infected water and the numerous deaths alleged to 
result from its use. I am not surprised at this ; but, seriously, 
if these offenders were really animated by a desire to do their 
neighbours still greater injury, I think I could put them up 
to a plan by which, with the aid of entozoa, they might deci- 
mate the population of the East-end of London, without 
any probability of their being “ brought to book” for it. 
And I may add that, perhaps, even Mr. Simon himself may 
not be fully aware to what extent entozootics may be propa- 
gated by sewage irrigation, or, for that matter, without it, 
whether intentionally or otherwise, by means of water. 
Let, therefore, the promoters of irrigation and the mem- 
bers of water companies alike pause before they sanction 
methods by which new organic impurities are likely to be 
introduced into the “meat and drink” of our teeming popu- 
lation. If, as Professor Tyndall demonstrated at the Royal 
Institution only yesterday, mere “pellucidity is no proof of 
the absence of soluble impurities” in water, it may also be 
said that clearness of water offers no proof of the absence 
of insoluble impurities, in the condition of germs of entozoa. 
One hundred tapeworm eggs in a glass of water would neither 
