there is but one conclusion that can be drawn therefrom-the increased mortality from typhoid and diarrheal diseases is due to the increase in the quantity of bacteria from the intestines of man, which our citizens are compelled to ingest at that time. The causal relation between the impure drinking water and this death rate is so evident that to my mind it is almost a criminal negligence to allow such an easily preventable condition of affairs to longer obtain in our midst; and it can be truthfully said that just so long as the inhabitants of this District are compelled to use Potomac water in its present state of pollution, from 200 to 250 lives will be needlessly sacrificed annually. Respectfully, yours, E. K. SPRAGUE, Passed Assistant Surgeon, Marine-Hospital Service. P. A. Surg. J. J. KINYOUN, United States Marine-Hospital Service, Washington, D. C. APPENDIX. Places and dates at which samples were collected by representatives of the United States Geological Survey, with the results of examination. Sideling Creek, 1 mile above its mouth. Fifteen-Mile Creek. 300 yards above Chesapeake and Ohio Canal crossing. Sept. 26 Colon bacilli. Town Creek, 200 yards above Chesapeake and Ohio Canal crossing.... Sept. 25 Do. Do. Sept. 27 Do. ...do.. New Creek, 200 yards above confluence North Branch Potomac. Wills Creek, above glass works, three-fourths mile above Cumberland. Sept. 29 Do. Sept. 28 Do. Little Capapon Creek, one-half mile above mouth.. Sept. 29 Do. Great Capapon River, one-half mile above Baltimore and Ohio Rail- ...do ... Do. Sleepy Creek, near Baltimore and Ohio bridge, 1 mile above Sleepy Discharge from Berkeley Springs sewage pool into Warm Spring Warm Spring Run, below Baltimore and Ohio station, Hancock, W.Va. North Fork of Shenandoah River, Riverton, W. Va., 1 mile above confluence. Opequon Creek, West Virginia, near mouth into Potomac River. .do.. ..do Oct. 9 Colon bacilli. Sewage bacteria. Town drain, where it enters Marsh Run, Hagerstown, Md. ....do Do. Cedar Creek, three-fourths mile above confluence with North Fork Oct. 12 Antietam Creek, near mouth. ..do Do. Carroll Creek, near mouth into Monocacy, drainage of Frederick, Md. Oct. 14 Places and dates at which samples were collected, etc.-Continued. Places. Date. Bacteria. Catoctin Creek, Virginia, one-half mile from mouth. Monocacy Creek, Maryland, one-fourth mile from mouth.. Shenandoah River, at junction with Potomac, Harpers Ferry side. Potomac water, above Johnston Street Bridge, Cumberland, Md. Potomac River, one-eighth mile above junction with Savage River.. The latter inquiry was more particularly directed to the detection and isolation of two groups of bacteria-the colon and sewage groups-than to the general biology of the Potomac River water, because of the relation that these bacteria bear to disease. The colon bacillus taken in connection with others of this group has been regarded as an index of water pollution, and while these are not considered as the specific causes of disease, they are always found associated with those that are. So far as known, the typhoid bacillus has been isolated only twice from drinking water, notwithstanding the fact that this one bacillus has been sought for more than all others combined. Various explanations have been given as to why this bacillus can not be detected and isolated, even from water which is positively known to contain it; yet none are fully satisfactory. The most plausible theory is that the other bacteria are so numerous as to obscure it. This seems to be the case in isolating the typhoid bacillus from dejecta. The colon bacilli and other intestinal bacteria are so numerous that the tpphoid bacillus is recognized with great difficulty. If this, then, be the case, one can readily imagine the difficulties in the way of success in isolating the typhoid bacillus from water where the sewage is greatly diluted and the bacterial flora is so varied and numerous. Dr. Dunham has shown that many of the bacteria found in sewage possess the power of living and multiplying in an atınosphere devoid of oxygen; also that this method is very valuable in detecting sewage contamination when it would be extremely difficult to do so by other means. Dr. Sprague has employed this method in his investigations and found it highly satisfactory. This method is valuable in detecting the presence of sewage in infinitesimal quantities, and is far more delicate than chemical methods. Of course, the detection of the biological factors in sewage is meant, and not chemical compounds. Chart No. I of Dr. Sprague's report shows the relative quantity of sewage pollution found. Dr. Theobald Smith was first to make a quantitative determination of the bacteria in the Potomac water. The results of his inquiry may be seen in the accompanying chart No. B. By comparing this chart with the one submitted by Dr. Sprague it will be seen that there is a considerable variance in the results. Especially is it so with reference to the relation the number of bacteria bear to the presence of typhoid fever. This difference is thought to be due to the changed conditions which have taken place within the past twelve years. My own observations during the past four years more nearly coincide with those of Dr. Sprague than with those of Dr. Smith. The most striking feature is the number of times the colon bacillus was detected DIAGRAM SHOWING THE SEMIWEEKLY VARIATION IN THE NUMBER OF BACTERIA IN ONE CUBIC CENTIMETER OF POTOMAC WATER. SHADED, AEROBES. BLACK. ANAEROBES. |