60 Dr. Herschel on the Nature and Construction 
which I answer, that in the decomposition of phosphoric fluids 
every other ingredient but light may also return to the body 
of the sun. And that the emission of light must waste the 
sun, is not a difficulty that can be opposed to our hypothesis. 
For as it is an evident fact that the sun does emit light, the 
same objection, if it could be one, would equally militate 
against every other assignable way to account for the phse- 
nomenon. 
There are moreover considerations that may lessen the pres- 
sure of this alleged difficulty. We know the exceeding sub- 
tilty of light to be such, that in ages of time its emanation 
from the sun cannot very sensibly lessen the size of this great 
body. To this may be added, that, very possibly, there may 
also be ways of restoration to compensate for what is lost by 
the emission of light ; though the manner in which this can 
be brought about should not appear to us. Many of the ope- 
rations of nature are carried on in her great laboratory, which 
we cannot comprehend ; but now and then we see some of the 
tools with which she is at work. We need not wonder that 
their construction should be so singular as to induce us to con- 
fess our ignorance of the method of employing them, but we 
may rest assured that they are not a mere lusus naturce. I al- 
lude to the great number of small telescopic comets that have 
been observed ; and to the far greater number still that are 
probably much too small for being noticed by our most diligent 
searchers after them. Those six, for instance, which my sister 
has discovered, I can from examination affirm had not the 
least appearance of any solid nucleus, and seemed to be mere 
collections of vapours condensed about a centre. Five more, 
that I have also observed, were nearly of .the same nature. 
