6 tlMEHftl. 
the marked effe6l upon the appearance of the spirit 
noticed upon dilution. Nor could we believe that there is 
any likelihood that Liverpool well water would affe6l the 
refra6live power of alcohol to a different extent than dis- 
tilled water does, but it is well known that many rums 
will remain clear after mixture with distilled water which 
become opalescent with Liverpool well water. 
If Mr. Veley'S explanation of the cause of cloudiness in 
the diluted rum is corre6l, a similar effe6l would be pro- 
duced by other liquids having indices of refra6lion differing 
from the spirit. We have mixed " faulty" rum (that ex- 
amined by Mr. Veley) with glycerin, which has an index 
of refra6lion of i'478, in proportions of one of rum to two 
of glycerin, without any " fluorescence" being produced. 
In the case of water the difference between the refra6live 
indices of the strong and the dilute spirits is about '015 
while in that of the glycerin it is about '078 ; if the micro- 
organism theory is correft, the latter mixture should be 
the more " fluorescent" or cloudy, but it is not so, it re- 
mains absolutely clear. 
This, however, being susceptible of explanation by the 
assumption that the organism has a higher power of 
refra6lion than has the spirit, the index of refra6lion of 
the latter being just high enough to render the microbe 
invisible in the not diluted rum, we, therefore, submitted 
it to another test. 
By the addition of glycerin in the proportion of 12^ 0/0 
to the diluted " faulty" rum the index of refra6lion of the 
diluted rum is brought back to that of the original 42 o.p. 
spirit, and therefore, if the cloudiness is a ** fluorescence" 
due to the presence of a micro-organism having the re- 
fra^ive power which the strong spirit has, it would dig* 
