mei. Nee. 
FRIDAY, MARCH 14, 1884. 
COMMENT AND CRITICISM. 
Ir one wishes to study man, it may be desir- 
able to seek large cities, where men abound in 
great numbers and in almost infinite variety ; 
but, if nature is to be questioned and cross- 
examined, it is wise to betake one’s self to the 
fields, the woods, and the mountains, over 
which the artificial has not yet gained control. 
In the study of various problems in terrestrial 
physics, it is of the utmost importance to 
place the observing-stations so that they may 
fairly represent general conditions, and not be 
influenced by merely local disturbances; and 
it has long been customary to give such con- 
siderations proper weight in the selection of 
points at which various physical constants are 
to be determined. An article in the present 
issue, on the exposure of thermometers, fur- 
nishes evidence that it is quite possible for 
large cities to be fortunate in the possession 
of a climate which is largely artificial; that a 
meteorology which is based on observations 
taken under such artificial or peculiar con- 
ditions is likely, now and then, to go astray ; 
and that in physics, as in politics, it is some- 
times safe to await ‘ returns from the coun- 
try.’ 
If the earth be represented by a globe six- 
teen inches in diameter, the largest city in 
the world will hardly be visible to the naked 
eye; and yet in most large cities there will be 
found to exist a set of meteorological con- 
ditions differing considerably from those of 
the surrounding country. It is not likely that 
difference exists alone in temperature, or that 
itis not noticeable, and worthy of serious at- 
tention, in other elements which go to make up 
‘the weather ;’ and it would appear desirable 
for working-meteorologists to agree upon some 
systematic plan of investigation which might 
No. 58. —1884. 
result in the determination of the proper loca- 
tion and exposure of their instruments, that 
they may more truthfully exhibit the average 
condition of the area which they represent. 
Tue close connection and interaction of re- 
ligion, statescraft, and science in the modern 
world is illustrated in an interesting way in a 
recent number of the Proceedings of the Royal 
society of London. ‘The British government, 
desiring to introduce cheese-making as an In- 
dian industry, was met by the difficulty that 
the religious beliefs of a large portion of the 
population of India placed an absolute veto on 
the use by them of cheese, in the manufacture 
of which rennet obtained from the stomach of 
an animal had been employed. ‘The leaves of 
a species of Pinguicula are used by the Laps 
to coagulate reindeer-milk; and the govern- 
ment circulated in India a request for informa- 
tion as to any Indian plant which was known 
to have a similar property. Surgeon-Major 
Aitchison called attention to Withania coagu- 
lans, a Himalayan and northern India plant, 
the seeds of which were said to coagulate milk. 
A quantity of this material was sent from Kew 
to Mr. Sheridan Lea of Cambridge for exami- 
nation. He was able to extract from it a fer- 
ment identical with the rennet ferment of the 
gastric mucous membrane of animals, and 
capable of preservation in solution as a com- 
mercial article in a similar way. The ferment 
exists in the seeds in considerable quantity, and 
is readily and cheaply extracted from them. 
Or the ‘ change in the unit of time’ contro- 
versy, to which we alluded in a late issue, 
there seems as yet no likelihood of abatement. 
Originally begun by Mr. Stone, lately her Maj- 
esty’s astronomer at the Cape of Good Hope, 
it was at once participated in by Sir George 
Airy, the late astronomer royal, by Professor 
Newcomb, and later by a number of continen- 
tal astronomers. When the Royal astronomi- 
