THEO. S. VERY. 
the sanitary conditions were all that could be desired. And in this 
connection a word or two concerning a common error may not be un- 
mstructive. It has sometimes been taught, and very generally accepted, 
that an excess of carbonic acid in the air of a room or a building is the 
condition favorable for the production of disease. It is extremely 
doubtful if this is true. According to reports of 'experiments by Sir 
Humphrey Davy, a large percentage of carbonic acid may exist in 
respired air without producing positive physiological effects to the per¬ 
son inhaling it, and the percentage, even in the most crowded and illy 
ventilated apartment will seldom be found to exceed 0.5 per cent. So 
that a pei son or an animal might possibly receive the poison producing 
spinal meningitis, or other contagious disease, on the top of Mt. Washing¬ 
ton as in what is considered the vitiated air of city stables or dwellings. 
Our methods of arriving at conclusions in many cases have been 
hasty to say the least, and a great many accepted theories about which 
we have no doubt, because we do not think sufficiently, will not stand 
investigation and inquiry. I do not suppose that a difference in the 
proportions of oxygen, hydrogen, or carbonic acid in respired air would 
f avor the carrying of poisonous gases, vapors or dust, any more than a 
preponderance of ether, oxygen or hydrogen in the water of mineral 
springs affects their medicinal qualities. Possibly, through a chemical 
analysis of air, we may some time ascertain some of the real causes of 
pestilence which are not already known. 
I he result ol three post-mortem examinations of cases of cerebro 
spinal meningitis have failed to show me any softening or alteration in 
appearance of the spinal cord or its membranes, except of the medulla 
oblongata and its membranes. In all were the dorsal and lumbar por¬ 
tions apparently free from the effects of any disease. In the last one 
at which Mr. C- P. , Lyman, of Springfield, was present, we found un¬ 
doubted pus corpuscles in the pelvis of the kidneys, and under the pia- 
mater of the brain, portions of which were the same day examined by 
Dr. I readwell, ot Boston, under the microscope, at which examination 
we were also present. In Prof. Williams’ work on Veterinary Medicina, 
may be found a very interesting article from the pen of Mr. Lyman, 
which contains views regarding the etiology and pathology of the dis¬ 
ease, similar to those expressed by Prof, i^arge. I have thus far had 
twenty cases of cerebro spinal meningitis this spring, of which all have 
made good recoveries, except one which died the second day. To 
none, except that one, has any external application been made, except 
additional clothing in cases of clipped horses. 
