nerves of the orbit of the eye. 301 
The eighth, and the Accessory nerve, are respiratory 
nerves. 
The ninth nerve is the motor of the tongue. 
The tenth is the first of the spinal nerves ; it has a double 
root and a double office ; it is both a muscular and a sensi- 
tive nerve. 
Had I taken the nerves of any other complex organ rather 
than of the eye, I should have had an easier task. If I had 
taken the nerves of the tongue, I should have been able to 
prove by experiment, and in a manner the most direct, that 
the three nerves belong to three distinct functions, and stand 
related to three different classes of parts. I could have shown 
that taste and sensibility belong to the office of the fifth nerve, 
voluntary motion to the ninth, and deglutition to the glosso- 
pharyngeal nerve of the tongue. 
In concluding these papers, I hope I may be permitted to 
offer a few words in favour of anatomy, as a means better 
adapted for discovery than experiment. The question lies 
between observation and experiment, and it may be illustrated 
by astronomy and chemisty. In the first, the objects being 
beyond the influence of man, he makes observations, not 
experiments ; and the science at length attains a state of 
perfection which raises our estimate of the human intellect. 
In the latter, for the most part, the subjects lie out of the 
sphere of mutual influence ; they must be brought together 
by artifice, and chemistry becomes a science of experiment. 
But anatomy is more allied to the former than to the latter 
