668 ON THE ANALOGY BETWEEN THE GRIPES 
terposition, and to be contained comparatively harmlessly there, 
until it can be removed by the absorbents, when, from some cause 
of irritation, an undue quantity has been poured out. 
The Mediastinum. —The reflection from the sternum upward 
and the spine downward is called the mediastinum. It evidently 
consists of a duplicature of pleura, or the unattached or reflected 
membrane on each side, and between these membranes we find 
the heart securely lodged ; but its situation and connexions, and 
the advantages derived from them, belong to another system. That 
portion of the mediastinum anteriorly which is not thus occupied 
is called the anterior or little mediastinum , the contents of which 
have been already described ; and behind is the posterior or great 
mediastinum , containing the gastric portion of the oesophagus, the 
posterior aorta, the posterior cava, and a kind of fold in which is 
wrapped the larger of the two lobules of the right lung. 
We are now prepared to return to the intimate structure of the 
lung itself; but this is an important subject, and deserves a sepa¬ 
rate lecture. 
ON THE ANALOGY BETWEEN THE GRIPES IN 
HORSES AND THE EPIDEMIC CHOLERA. 
By Bracy Clark, F.L.S ., Member of the Royal Institute of 
France. 
In the midst of the numerous, opposite, and very conflicting 
opinions, which prevail at this time respecting the direful epide¬ 
mic called cholera, and which still exerts its fatal ravages in spite 
of all that has been done, and which opinions respecting its nature 
and its treatment seem almost as various and unsettled as they 
were at the first commencement of it (if we may judge, at least, 
from the recommendations every day proposed in the medical pe¬ 
riodicals). 
Under these circumstances you will, perhaps, pardon the sug¬ 
gestions of one who, though formerly educated for it, is not now 
strictly one of your honourable profession, and permit him to ad¬ 
vance an opinion which he has long entertained, and which, if it 
be not founded on truth, has one merit at least—that of novelty. 
These opinions have, however, been shewn to a few of his medi¬ 
cal acquaintance, who do not see any thing in them to forbid the 
reasonings and conclusions here drawn ; which has induced him 
—with great deference, however—to make them more publicly 
known. If they should be at all admitted, they will certainly 
lead to a more decisive, and perhaps more successful, mode of 
treating this disease. 
