will, one on each side near the front, and one above the rear doors. The signs "Health Department" in front and "Ambulance" on the sides are removable. The vehicle is made for both pole and shafts and weighs about 900 pounds. It is fitted with a stretcher with removable covers, and two seats that can be folded out of the way. Through the courtesy of Sister Beatrice we have been able to secure treatment of patients at Providence Hospital who would not otherwise have been able to obtain proper nursing, etc. With the two wards for which appropriation was made at the last session of Congress, we will be better able to cope with the disease and may look for a reduction in the death rate among the poor. It is an interesting fact that of the 110 deaths from diphtheria, in 16, or 15.4 per cent of them, the nature of the disease was only discovered after the death of the patients, when the medical sanitary inspector obtained cultures from the corpse. The causes of death given by the attending physician on the death certificates were as follows: In few, if any, of these cases were precautions taken as to the isolation of the patient or disinfection, so that it can be readily understood how difficult it is to control the disease. I have been able to trace several cases of diphtheria to some of these so-called cases of membranous croup. Scarlatina.-During the year there has been but one death from scarlet fever, with a mortality in 160 cases of only 0.6 per cent. This is most remarkable, and is not equaled in any of the fifteen representative cities shown in Table V. In those cities the death rate has varied from 8.5 per cent to 2.1 per cent, which is the nearest approach to our recent low mortality. The disease has been of an extremely mild character. Some of the cases presented an appearance so slightly resembling scarlatina that the diagnosis was almost doubted, but the tedious desquamation which followed proved conclusively its accuracy. TABLE V.-Number of reported cases and deaths from scarlatina, together with ratio per 10,000 of population, in fifteen representative cities during the year ending June 30, 1897. Boston.. Detroit Baltimore Buffalo Pittsburg. Cleveland. Omaha... Atlanta.. Washington. Milwaukee New Orleans.. 101 89 72 89 27 17 43 22 6.5 7.5 6.4 508, 694 72 42 53 81 157 176 185 154 228 281 332 206 1,967 38.6 168 3.3 8.5 1,962, 319 213 144 107 327 395 496 785 667 767 789 1,029 742 6, 461 32.9 425 2.1 1, 201, 524 64 45 53 95 103 146 221 232 367 403) 490 512 2,731 22.7 207 1.7 267, 500 41 20 42 31 55 66 71 46 36 30 35 71 544 20.3 35 1.3 506, 398 35 28 31 66 92 118 119 83 117 102 350,000 30 30 16 49 49 52 52 56 72 66 286, 250 31 51 54 63 55 41 35 14 13 22 340, 139 20 18 13 30 28 44 29 16 11 14 140, 000 1 2 5 19 14 11 8 7 14 20 105, 000 6 2 6 8 3 6 2 7 6 277, 782 8 8 4 13 19 20 32 19 11) 6 360,000 5 10 4 16 12 33 22 9 14 21 4 7 8 10 10 14 8 6 8 4 267, 500 275,000 2 9 19 6 2 12 8 7 9. 3 981 19.3 48 94 4.8 633 18.1 20 .57 3.1 423 14.9 16 55 3.8 288 8.4 6 .17 2.1 3 6 110 7.9 8 .57 7.6 11 12 76 7.2 9 .85 11.8 10 10 160 5.7 1 .03 0.6 13 10 169 4.7 6 16 3.5 10 16 105 3.9 71 261 6.6 5 4 86 3.1 1 1,619, 226 (a) (a) (a) (a) (a) (a) (a) (a) (a) (a) (a) (a) (a) a No report of cases. 2 77 (a) .07 .47 2.3 TABLE VI.-Number of cases and deaths from scarlatina during the fiscal year 1896–97. TABLE VII.-Number of cases and deaths from scarlatina, by ages. 7.7 1 6 APPENDIX B. REPORTS OF THE CHEMIST. WORK IN THE CHEMICAL LABORATORY. SIR: I have the honor to submit the following report relative to the work performed in the chemical laboratory for the fiscal year ending June 30, 1897: During the year I have made 588 analyses, as follows: Water. Considerable attention has been given to the examination of water from the public and private wells, it being a well-recognized fact that impure water is one of the fundamental sources of disease. In all, 185 samples of water were examined, as follows: From public wells, 115; from private wells, 65, and of Potomac water, 5. As the result of these analyses, 13 of the public wells were condemned, 2 were reported as suspicious, while 2 others were recommended to be cleaned. Of the private wells, 19 were condemned, 9 were reported suspicious, and 4 were recommended to be cleaned. The percentages of impure waters would be 14.7 for the public wells and 49.2 for the private wells. This large excess in the percentage of impure waters from private over public wells is due evidently to the limited depth of the former, and to the fact that they are not sufficiently protected from surface drainage. The analyses of these two classes of waters show a marked difference, the nitrogen in the form of free and albuminoid ammonia being almost entirely absent in the waters from the public wells, whereas in the waters from private wells it is in general the most prominent constituent, and is usually excessive. The inference to be drawn from this will be more clearly understood when we consider the manner in which these various nitrogenous compounds are produced. In the examination of a sample of water we are accustomed to estimate the amount of nitrogen present existing in four distinct conditions, and as the result of those estimations base our knowledge to a large extent on the character of the water. Those conditions would represent nitrogen in the form of free and albuminoid ammonia, and in the form of nitrites and nitrates. The nitrogen existing in the form of albuminoid ammonia represents the presence of actual nitrogenous organic matter, while the other forms represent the various stages of nitrification. It is unnecessary to enter here into any extended discussion as to how this nitrification is accomplished other than to state that this process is brought about by a species of nitro organisms, and that in general there are three distinct genera comprising, first, those organisms which convert nitrogenous organic matter into ammonia or carbonate of ammonia; secondly, those organisms which transform carbonate of ammonia into nitrous acid, and, lastly, those organisms which convert nitrous into nitric acid. Each of these germs seems to be necessary to convert the organic nitrogenous matter into the form of nitric acid, which would represent practically the final state of oxidation, or the last step in the purification of a water. More important, however, is the fact that these bacteria, which convert nitrogenous organic matter into ammonia or carbonate of ammonia, are usually found in surface soils and in the air and rain water, and that they flourish most abundantly at a temperature of from 85° to 95° F. At this point we might readily conclude that those waters containing considerable quantities of free and albuminoid ammonia were of surface origin were it not for the fact that waters of deep origin are liable to become polluted with albuminous matter, thus rendering such discrimination impossible. We must therefore take into consideration one other element which plays an important part in judging of the history of a water, namely, chlorine. This element is considerably increased by the presence of decomposed animal matter or human excreta, whereas growing vegetation has a tendency to remove it from its solution. The absence of any considerable quantity of this element, therefore, taken in connection with considerable free and albuminoid ammonia would be a strong indication of surface water. Sulphur, likewise, is found to be a constituent of many forms of organic matter, which, in its partial oxidized state, gives rise to sulphureted hydrogen, and while this compound is often formed from iron pyrites, by the action of water, yet the absence of any considerable quantity of iron compounds would strengthen the conviction that its origin was organic, and would lead us to the conclusion that waters of the nature indicated above were of surface origin and therefore liable at any moment to become polluted. It should be remembered, however, that the presence or absence in waters of these chemical elements has little to do in themselves with the sanitary condition of a water, and that more depends on a correct interpretation of an analysis than on the analysis itself. Many waters have been probably unjustly condemned simply because the same were high in chlorine and nitrates, without considering whether these elements were derived from an organic or mineral source. Waters which flow through lime regions are liable to become impreg nated with nitrogen in the form of nitrites and nitrates, and yet the waters may be absolutely pure from a sanitary standpoint. Yet these elements are an index of the purity of a water, and when the interpretation is correctly based on the facts presented, then will the con It will thus be seen that standards can not well be used for determining the quality of a water, and that common sense and good judg ment on the part of the analyst are essential. Analyses of foods.-The following table shows the extent to which adulterations were found to exist in certain food stuffs and the result of prosecutions of such adulterations: Condensed milk.-Several samples of condensed milk were analyzed during the year with the following result: On the assumption that 3 per cent of fat is equivalent to 12 per cent of milk solids, it will be seen that practically one half of the total amount of solids is derived from the milk, the other half being due to added sugar. No preservatives other than sugar were found. Milk.-As previously stated, 244 samples of milk were examined during the year, 75 of which were collected at the Baltimore and Ohio depot, 62 at the Baltimore and Potomac depot, 75 collected about the city, and the remainder submitted by private parties. In general it might be stated that the condition and quality of the milk as furnished to the consumer has continued to improve, and that only two cases were met with where it was deemed expedient to take the parties into court for selling adulterated milk. Perhaps the greatest improvement noticed in this connection is in the condition of the dairies, and while there is still room for considerable improvement, yet the condition of the dairies to-day is far superior to what they were two years ago, and we can not, therefore, but believe that further efforts in this direction will result in great good to the public generally. It is essential, however, that there should be a law regulating the temperature at which milk shall be kept and sold. This is, in my opinion, one of the most important considerations relating to this subject, and should receive early attention, for while the majority of dairymen |