SCIENTIFIC SUMMARY. 
32D 
recently made by Mr. Wanklyn, at the Society of Medical Officers of 
Health, one of which concerned the purification of water supposed to con- 
tain the germs of typhoid fever. The following quotation from Dr. Tripe’s 
letter will fully explain his position and that of Mr. Wanklyn: — “I 
attended the meeting, but arrived too late to hear Mr. Wanklyn ’s speech 
but was informed that he had stated that the non-detection of albuminoid 
matter, by Nessler’s test, after distillation of filtered water with an alkaline 
permanganate, was strong proof of the absence of typhoid germs. The issue 
thus taken is one of the greatest importance, because if Mr. Wanklyn’s 
statement be true, the most polluted water can be rendered potable and in- 
nocuous by filtration through a moderately thick bed of filtering materials. 
Certainly this statement is contrary to the opinions held by most other 
chemists, and if it be based on the absence of ammonia after distillation of 
the suspected water with an alkaline permanganate, the assumption is almost 
certainly erroneous, as Mr. Wanklyn himself admits that all the albu- 
minoid matters are not converted into ammonia by his process. He would 
appear to have made this statement without knowing the size of the minute 
organisms which are suspected to be typhoid germs, otherwise he could not 
have placed any reliance on the Nessler test. Dr. Klein says that they 
are one- third the size of the blood corpuscles of man, but his engravings 
show them to be much smaller, and to possess only about one-sixth the area 
of a blood-disc. Now if they are similar to bacteria in their mode and 
rapidity of increase, it would be only necessary for a very few to obtain 
admission into the human body to set up their specific action, provided the 
person were susceptible to their influence. Does Mr. Wanklyn say that he 
could detect by the albuminoid ammonia process a dozen of these, which are 
less than the total bulk of one blood corpuscle, in half-a-pint of water ? 
and if not, where is his argument ? ” 
METALLURGY, MINERALOGY, AND MINING. 
Compressed Peat. — u Silliman’s American Journal ” states that peat pressed 
into blocks and made so compact that a cubic foot weighs 85 to 100 pounds, 
is manufactured by Mr. A. E. Barthel, of Detroit, Michigan, and sells for 
one and a half dollars per ton. 
The Neiv Metal Gallium . — At a meeting of the French Academy the 
Secretary opened a sealed note deposited by M. Lecocq de Boisbaudran, the 
first paragraph of which reads thus : — 11 Day before yesterday, on Friday, 
the 27th of August, 1875, between three and four o’clock in the afternoon, 
I obtained indications of the probable existence of a new simple body 
among the products of the chemical examination of a blende coming from 
the mine of Pierrefitte, valley of Argeles, Pyrenees.” The evidence relied 
on to prove this discovery, a part of which evidence was given in the sealed 
note and another part in a note read at the same meeting, is : (1) the oxide 
(or perhaps a basic salt) is precipitated slowly by metallic zinc in a solution 
containing chlorides and sulphates ; (2) its salts are easily precipitated by 
barium carbonate in the cold ; and (3) it gives a spectrum showing two 
