374 EXPEKIMENT STATION RECORD. 



The c'oiiciusioiis wliicli wi^'o drawn follow: 



"A liomogeneous suspension of the bacteria of adult liunian feces may be 

 readily prepared by making it sufficiently dilute, 1 : 100. 



"In such a suspension the bacteria can be counted microscopically by an 

 experienced observer, with a fair degree of accuracy. 



"The gravimetric method of Strasburger for determining tlie quantity of 

 fecal bacteria is more time consuming, b\it the method is capable of a higher 

 degree of accuracy than the enumeration procedures. The separation of the 

 bacteria should be done by fractional sedimentation in a high speed centri- 

 fuge, and requires careful work at every step. 



"In the case of normal adult men, eating an ordinary mixed diet, the aver- 

 age number of fecal bacteria excreted daily is about 33X10"; the average 

 daily bacterial dry substance about 5.34 gm., and the daily bacterial nitrogen 

 0.585 gm., making up 4(j.3 per cent of the total fecal nitrogen. There is consid- 

 erable individual variation in the average quantity of fecal bacteria even in 

 persons taking the same diet. 



" The results of enimieratiou do not correspond accurately with the results 

 of gravimetric determination of the bacteria under different conditions. The 

 fecal bacteria as individuals contain an amount of dry substance subject to 

 considerable variation. 



" The bacteria of the adult human feces are Gram negative for the most 

 part, about 70 per cent of all the bacteria being Gram negative bacilli. Gram 

 positive rods are constantly present. 



" It is possible to recognize microscopically a number of morphologically 

 different bacteria, present in such numbers that they must have resulted from 

 multiplication in the intestine. . . . Therefore there are several species of bac- 

 teria whose normal habitat is the human intestine. 



" Free spores are almost constantly present in considerable uvimber in the 

 feces. They are more numerous in dry stools as a rule. Diarrheal stools, 

 howev(>r, sometimes show a very large number of free spores. 



" Thin, flexible spirals are quite frequently present in normal stools, and 

 under some conditions are very numerous. 



" The direct quantitative determinations of the fecal bacteria furnish evi- 

 dence of the extent and nature of the bacterial growth in the intestine. This 

 seems to be a delicate index of intestinal conditions." 



Some observations on a twenty-four hours' walking race, F. Cook, E. G. 

 ScHLEisiNGER, aud A. H. Todd (Brit. Mp<L Jour., 1909, No. 2552, pp. 1526- 

 1528). — Cardiac condition, blood pressure, body weight, general appearance, 

 urine, and food were studied in connection with a 24-hour walking race at 

 Shepherd's Bush. London. September. 1909. The food taken during the race 

 varied somewhat, but without exception the competitors' previous diet did not 

 differ markedly from that of ordinary individuals. Nausea and other unpleas- 

 ant symptoms were observed after eating during the contest, which the authors 

 attribute to the use of carbohydrate foods, and they therefore recommend that 

 in a contest of this character little or no food be taken during the period of 

 physical exertion, though albumin water or some such preparation may be 

 given to avoid the depressing mental effect consequent upon withholding all 

 food. 



" Soldiers bearing heavy clothing and equipment have frequently marched for 

 many houi's with no food, jjrovided that a sufficiency of water is available. Ex- 

 periments on animals, too, show that external work can be performed for some 

 days on a water diet only." In other words, the individual should depend 

 for his severe exei-tion upon the energy derived from his previous diet rather 

 than from food taken during the period of work. 



