[29] To enable the reader more easily to understand Mr Dick's views of this disease, I have added a drawing of the foot of the sheep, which it may be well to consult before entering on the subject.
Fig. 4. Plate. I. Section of a toe:—c. c. Crust of the hoof; s. Sole; g. g. Gland which secretes the hoof.
[30] Fig. 5. Plate. I. Gives a view of the inner surface of the toe of a sheep, with the interdigital gland laid open.
g. The gland.
d. The duct of the gland, opening upon the anterior surface of the leg.
When the interdigital gland is much enlarged, it becomes necessary to cut it out. This ought to be a last resource, as the part appears to be of too much importance to be easily dispensed with.
[31] The sheep is more inconvenienced by Coryza than other animals, owing to the naturally small calibre of the nostrils, the inferior turbinated bone being of large dimensions, and occupying the greater part of the nasal cavity. It is from this peculiar formation of the nose, that sheep are so very easily blown, when made to exert themselves in running.
[32] It is quite possible that a sheep may die of true pulmonary consumption and yet have scarcely any cough.
[33] The examination of fluke worms is much facilitated by placing several of various sizes flat upon a slip of glass, and allowing them to dry in this position. On holding the glass between a bright light and a lens, and looking through the latter, the distribution of the vessels, and the position and form of the eggs, are beautifully displayed.
[34] The property of acting on organized matter, so as to convert it into substances similar to those which constitute the agent, is characteristic of a vital power.