It was found that whenever soldiers were thrown largely upon the use of hard bread, or army biscuit, as a diet, a peculiar train of abnormal manifestations presented themselves. These are : — 

1. Constipation. 

2. This constipation is preceded, accompanied and followed by fermentative changes and the development of intestinal gases and yeast plants (Saccharomyces and Mycoderma) in the food in the stomach and intestines. 

3. These fermentative changes are always worse towards evening and during the night, and go on increasing from day to day till : — 

4. Finally the gases and yeast plants and other products of fermentation developed, produce so much irritation, commotion, distention and paralysis of the intestinal walls, that diarrhoea ensues, which soon becomes chronic, and is not at aU amenable to the treatment of ordinary diarrhoeal conditions. 

5. Accompanying the fermentative changes is always a paralytic tendency, more or less strongly marked. This is manifested in the alimentary canal, and especially in the larger intestines ; next in the extremities, the legs prickling and " getting asleep," frequently, with ringing in the ears and a numb, mixed up or confused feeling in the head, etc. These are manifestations pertaining to the history of the disease known as Locomotor Ataxy.

6. A cough, accompanied by more or less hoarseness, usually sets in, especially during the night and on rising in the morning. It is also accompanied by the expectoration of a thick, cream-colored, sweetish mucus. 

7. This is followed by more or less constriction in breathing with frequently palpitation of the heart on any excitement. 

8. After the diarrhoea sets in, there is generally a remarkable tendency to fibrinous depositions in the heart (Thrombosis), and to the clogging up of the pulmonary vessels with fibrinous clots (Embolism), with pains and aches in extremities and back. 

9. The diarrhoea is not so likely to come on when the men are actively engaged, as it is when they go into camp and are less active. The active exercise seems to aid in working the starchy food out of the stomach into the bowels, where it is digested before it gets to fermenting badly. To demonstrate more positively that these abnormal conditions had their origin in the too exclusive use of Army biscuit as a food, it was determined to institute a series of experiments upon the exclusive use of this kind of food, as tried upon strong, healthy men, in a healthy locality, and free from the enfeebling influences of Army life. Accordingly, on arriving at Cincinnati, Ohio, I engaged the services of three strong, vigorous men of good habits and in the prime of life, for this purpose. The experiments were conducted with watchful care from day to day, and the results were most convincing and conclusive in favor of the previous observations made upon the soldiers, as will be seen from the following daily records of the experiments. , . , October 12th, at noon, began feeding the men exclusively upon Army biscuit. For drink used water, to which at dinner and tea about one ounce of good whiskey was added. Gave the men the whiskey, as they were used to taking about two or three drinks daily.

On the evening of the 9th, after giving my boarders a good beefsteak supper, I paid them off and discharged them from a diet drill to which they had submitted with a good grace for 28 days. These three subjects are all strong, healthy men in the prime of life, who had been used to the substantial diet of the active business men of our Western cities. From the commencement of the army-biscuit diet, up to the time when the discharges assumed a yeasty, chronic diarrhoea type, 19 days elapsed in one case, 18 days in the second and 20 days in the third case. The fermentative condition, and the production of alcoholic and acid yeast (Saccharomyces and Mycoderma), commenced and showed themselves in a marked degree on or about the 6th day, and increased until the army-biscuit diet was discontinued. 

The first abnormal condition brought about by this diet was constipation, with a partial suppression of the biliary and intestinal secretions and lessened peristaltic action. This left the alimentary matters in the stomach and intestines an unusual time, during which fermentative changes were started. This fermentative condition increased daily, till the alimentary canal became filled with alcoholic and acid yeasts in a state of rapid multiplication and development, disengaging large quantities of carbonic acid gas which distended the bowels with flatus. 

Just previous to the commencement of the diarrhoea and afterwards, there was a general paralytic tendency : this was especially marked in the intestinal walls, they losing their normal sensibihty and contractility under the irritant and poisonous action of yeast plants, carbonic acid gas, vinegar and other products developed during the fermentation of the amylaceous alimentary matters. In severe forms of the disease produced by this kind of feeding, the large intestines and sphincter become frequently so paralyzed that the feces pass involuntarily. About the time the diarrhoetic discharges commenced, there came on a huskiness and hoarseness of the voice, and a dry, constricted feeling about the larynx and pharynx. This was accompanied by a scalded, smarting soreness of the throat, as if it were inflamed, which extended into the bronchial tubes, together with the secretion of a thick, ropy, sweetish expectoration and considerable night and morning cough, with oppression and tightness about the chest. On examining the throat and larynx, the surfaces were found to be Avhiter than usual, showing that the parts were more deadened than inflamed.

This affection differed from all colds, it being caused by partial death or paralysis, instead of by over-action or inflammation. It continued while the diarrhoea lasted. There was also palpitation of the heart and oppressed breathing, on any excitement. I have noticed the same pulmonary derangement in all well-marked cases of chronic diarrhoea, or consumption of the bowels. During these experiments, the boarders were not allowed to perform any manual labor, or permitted to take any exercise besides the two to four mile walks, morning and evening. I was constantly with them, day and night, to observe all the symptoms and conditions ; to make such tests and microscopical examinations as were necessary to determine the various states and changes that were taking place and to indicate the latitudes and departures from the normal state. Had they been allowed to labor and take vigorous exercise, the fermentation and consequent consumption of the bowels would have been deferred to a later date. Vigorous exercise would have shaken and worked the food down out of the stomach into the small bowels, where it is digested, before any very serious fermentation had set in. Such as did set in, however, would have finally culminated in the disease as before, but under a much slower rate of progress. On the tenth day of the feeding, all the men began to show quite evident signs of semi-paralysis of the nerves of the extremities. This gradually increased until the army-biscuit diet was discontinued. During the last few days of the feeding the symptoms of locomotor ataxy were strongly marked, and the disease was progressing with alarming rapidity. The eyes were growing more and more dim, and the deafness and ringing in the ears were becoming strongly manifested.