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RM2AFJEMY–. Preventive medicine and hygiene. acticallythe best place is at somecentral station, where itmay be done scientifically under official surveillance. Methods of Pasteueization.—There are three well-known methodsby which milk may be pasteurized: (1) the flash method; (2) theholding method; (3) in the bottle. The fiash method consists of heating the milk momentarily to atemperature of about 178° F. (81° C.) and chilling at once. This methodis sometimes incorrectly called commercial pasteurization. It does notgive uniform results, is not entirely reliable, and does not meet withthe approval of th
RM2AFJPJE–. Preventive medicine and hygiene. direct ancestry of the germ cells ineach individual. The cells which make up thebodily structure may be regarded as the resultof so many offshoots which come to an end atthe death of the organism and have no progenyof their own. The minute study of the germ cells taken inconnection with modern experimental work onthe methods by which inheritance takes placeshows a strong tendency to confirm Weismannsviews, so far as the inheritance of distinct anddefinite characters is concerned. Wilson ^ has expressed Weismanns theory asfollows: It is a reversal of the true
RM2AFK18A–. Preventive medicine and hygiene. matter in the pits and then deposit it and feed upon the food prepared for the soldiers atthe mess tents. In some instances, where lime had recently been sprinkledover the contents of the pits, flies with their feet whitened with lime wereseen walking over the food. Vaughan subsequently stated that he con-sidered that about 15 per cent, of the cases of typhoid in the camps werecaused by fly transmission. Alice Hamilton ^ isolated typhoid bacilli from 5 out of 18 house flies captured in Chicago inthe privies and fence neara sick room. It has beenshown experime
RM2AFK04Y–. Preventive medicine and hygiene. Fig. 35.—The Little House Fly {Homalomyiacanicularis 6). (Hewitt.) FLIES 253 bacteria on flies are comparatively small, while later the numbers arevery large. The places where flies live also determine largely the num-ber of bacteria they carry. The average of the 415 flies was about oneand one-quarter million bacteria. The method of the experiment wasto introduce the flies into a sterile bottle and pour into the bottle aknown quantity of sterilized water, then shake the bottle to wash thebacteria from the body of the fly. The numbers, therefore, only repre-s
RM2AFJADP–. Preventive medicine and hygiene. s of events constitutingthe nitrogen cycle largely depends upon the plant kingdom. The im-portant phases of the cycle occur upon the soil and in its superficiallayer. It will presently bo seen that this cycle has a fundamental im-portance in sanitary science, and lias a special significance in prevent-ing soil pollution, in the purifieation of water, and in the disposal of 774 GBNEEAL CONSIUEEATIONS sewage. It is evident that any permanent break in this cycle wouldresult in the cessation of life upon the earth. As soon as an animal or plant dies its protein c
RM2AFHJ07–. Preventive medicine and hygiene. ecessary for his comfort and health. Allarticles of equipment must be of good quality, of greatest strength andbest wearing power, with the least possible weight. There then remainsthe very important problem of distribution on his person so as to becarried with the minimum muscular exertion and fatigue. In all armiesthis problem is given much attention. 1228 MILITABY HYGIENE German experiments applied to the respiratory capacity of soldiershave shown that their loads, including overcoats, should seldom exceed 55pounds. The weight of the equipment of various n
RM2AFJ7FJ–. Preventive medicine and hygiene. ities having an abimdantwater supply. This danger was well shown in the studies upon typhoidfever in the District of Columbia, in which many of the shallow wellssituated within the city limits were shown by chemical and bacterio-logical analyses to be polluted. Wells may be disinfected with lime, which has been found to befairly effective. A mixture of carbolic acid and sulphuric acid in suffi- SOURCES OF WATER 815 cient quantity will sterilize a well, but these substances have evidentobjections. The method of injecting steam under a pressure of twoatmosphe
RM2AFJFD4–. Preventive medicine and hygiene. ian. Almost all countries prohibit the use of such foreign substances.The only proper preservatives for milk are cleanliness and cold. Dirty Milk—Tlie Dirt Test.—Practically all milk contains more or MILK 569 less dirt. For the most part, this dirt consists of cow feces. The pres-ence of dirt may best be determined by filtering a pint of milk tlirougha little disk of absorbent cotton. This produces a stain varying in inten-sity from a yellowish to a brownish or black spot. A Gooch crucible,a Lorenz apparatus, or simply an ordinary funnel may be used to filter
RM2AFJYYN–. Preventive medicine and hygiene. Fig. 35.—The Little House Fly {Homalomyiacanicularis 6). (Hewitt.) FLIES 253 bacteria on flies are comparatively small, while later the numbers arevery large. The places where flies live also determine largely the num-ber of bacteria they carry. The average of the 415 flies was about oneand one-quarter million bacteria. The method of the experiment wasto introduce the flies into a sterile bottle and pour into the bottle aknown quantity of sterilized water, then shake the bottle to wash thebacteria from the body of the fly. The numbers, therefore, only repre-s
RM2AFK30J–. Preventive medicine and hygiene. crawl under boards or stones, or into dry manurecollected under platforms or the like. This tendency of migrating ap-pears three or four days before pupating. The larvae leave the moist 250 INSECT-BOENE DISEASES manure for a dry, dark place. This migrating habit is of great advan-tage in that the winged tly, at the time of emergence, is thus affordedan easy path to freedom. Advantage may be taken of this migratinghabit to trap many larvae. They should be driven out of the manure pile by moistening it andtrapped in a basket or box, ordrowned in water. Life His
RM2AFHM7D–. Preventive medicine and hygiene. Normal colorsense. Teeth.—The teeth must be serviceable and should be reasonably freefrom peridental trouble which may lead to secondary and serious infec-tions. The actual number of teeth is less important than good occlu-sion. Unless four pairs of teeth oppose, it is a cause for rejection. Itmust be remembered that the field service ration is apt to be not wellcooked. False teeth may be lost or broken. Caries should be cor-rected before enlistment, for the Army dental surgeons are overworked.^Jour. A. M. A., March 17, 1917, LXVIII, No. 11, p. 841. 1190 MILI
RM2AFHNTR–. Preventive medicine and hygiene. in the box E for protection, andthis is placed in the chamber or in the inside of bundles to be disin-fected. The insulated wires from F and G are connected with a batteryand bell. As soon as the temperature reaches 100° C. the little metalstick melts, the contact is made between B and C, and the bell rings.This form of thermometer is more accurate than the pyrometers, whichdepend upon the contact being made by the unequal expansion of a com-pound metal bar, for the reason that moisture collects upon the electrodesand an electric contact is sometimes made bef
RM2AFK2XX–. Preventive medicine and hygiene. FiG. 31.—PuPARiuM OF House Fly. brewers refuse (spent hops), etc.house fly, but have a sharp, needle-like proboscis,sively on mammalian blood and are a great annoyance to horses andcattle in late summer and autumn. They bite persons less frequently,but are of importance onaccount of their possiblerelation to poliomyelitis,anthrax, etc. The sta-ble fly can best be con-trolled by eliminating itsbreeding places. Flies as MechanicalCarriers of Infection.—Leidy in 1864: attributedthe sjDread of gangrenein hospitals during theCivil War to the agencyof the house fly
RM2AFJYWG–. Preventive medicine and hygiene. rriman, also Jour. Hyg., 1914, XIV, 23. FLIES 255 and capable corps of inspectors Avith sufficient authority to enforce theregulations. The suppression of flies by voluntary effort through theslow process of education cannot be relied upon. In cities, stable manure should be jDlaced in properly covered recep-tacles and removed at least once a week. This one measure obviates theuse of kerosene, chlorid of lime, Paris green, or arsenate of lead, all ofwhich are expensive and uncertain unless used frequently and in liberalamounts; further, they decrease the fert
RM2AFJ0B2–. Preventive medicine and hygiene. in a recognizeddeterioration of property values. The processes nsed for the treatmentof sewage not infrequently result in odors that may be objectionable overconsiderable areas. Where the treatment works are entirely covered, as 974 SEWAGE DISPOSAL some kinds of works may be, little or no nuisance may result, butwhere, for example, the sewage is first submitted to putrefaction in aseptic tank and the septic effluent then sprayed into open air upon thesurface of sprinkling filters, this exposure of the atomized liquid resultsin the liberation of odors that may
RM2AFJY5G–. Preventive medicine and hygiene. Fig. 35.—The Little House Fly {Homalomyiacanicularis 6). (Hewitt.) FLIES 253 bacteria on flies are comparatively small, while later the numbers arevery large. The places where flies live also determine largely the num-ber of bacteria they carry. The average of the 415 flies was about oneand one-quarter million bacteria. The method of the experiment wasto introduce the flies into a sterile bottle and pour into the bottle aknown quantity of sterilized water, then shake the bottle to wash thebacteria from the body of the fly. The numbers, therefore, only repre-s
RM2AFHJMC–. Preventive medicine and hygiene. >? UO140SS 3^09-. s 3 UIDJ I IDlldSOWJ./i.M±il.iiiiiiMrii JQU!OJJ |D4!dSOH pQS!ACX^LU|
RM2AFK9JH–. Preventive medicine and hygiene. n. Sacco got only a local eruption by inoculating smallpox on theeighth to the eleventh days, and none after that. Vaccination protects not only against smallpox, but also against vac-cinia. Curiously enough, the degree and length of immunity appear tobe greater against smallpox than against itself. It is irrational to at-tempt to fix a definite time for the.duration of the immunity. Thisvaries as in other infectious processes. It is known through experimentand experience that the immunity gradually wears off. Definite protec-tion on the average lasts about s
RM2AFJ2G7–. Preventive medicine and hygiene. t that infection tookplace at this time. Professor Smith found that 96 per cent, of the casesthat occurred were in the districts supplied with water from the DawsonLake. (Whipple.) This outbreak again illustrates the resistance of the typhoid infectionto freezing, and the danger from a surface supply that for years may runsatisfactorily. Even the storage reservoir failed in this case, as in tliePlymouth ease, to check the quick transfer of the infection. Had the 940 WATER AXD ITS EELATIOX TO DISEASE Dawson supply beeu filtered or otherwise jDurified the epide
RM2AFJH64–. Preventive medicine and hygiene. 00 bacteria per cubic centimeter,and should not be more than thirty-six hours old when delivered. Inspected Milk.—This term should be limited to clean, fresh milk ^ See annual reports of this Association, also Public Health Reports, No. 85,May 1, 1912. MILK 5G5 from healthy cows, as determined hy the tuberculin test and physicalexamination by a qualified veterinarian. The cows are to be fed, watered,housed, and milked under good conditions, but not necessarily equal tothose prescribed in the production of certified milk. Scrupulous cleanli-ness must be exerci
RM2AFK6DX–. Preventive medicine and hygiene. 2 c 03 ? o.S - a O ^ r^ .-i c -So o a C T3 a fc o « ^ c o 1^ s QJ n +^ « o tn 1 1 -o o 3 o c r, O ^ c3 ^ ?t: S a a. EC ^ a ?•^ t< 03 s M 03 (4 ni J3 K - ff tao x T c3 0 f% OJ ^ Si a a; 3 •ao c ^1 ? ^< ^ ,,—^ c is tl n- «3 rn OJ o ^ s; s O c 3q3 a 0 in 3 -d rr -c f4 0 -*^ X 03 >> O a o; 0 > >J 1 o £ a o aS ^ 3 03 Hi o b - > O rp >, c3 M O o iC -3 JS o t- 0 o 03 J3 0 -S « . © 3>>-C O ?3 Ol ® !« » 0 R 3 >- S S m ^ o 3 ir 00 pj PL, 0 -< C-^ r , ?=• ^ 7J CD 03 ^ H 1 mc3 m 3 00 10.disePruforonlj RABIES 39 smallpox patients are n
RM2AFJAXX–. Preventive medicine and hygiene. l perforations, the widenedend of the conical opening debouching on the interior of the wall. Theholes through the bricks are about 2/10 inch in diameter externallyand 11/4 inches internally. Tobins tube consists of a large upright tube, about 5 or 6 feethigh, which conducts outside air into the room through the wall. The Sheringham valve is a small vertical flap door in the wall nearthe ceiling, balanced by a counterpoise, and hinged so as to fall forward VENTILATION 761 toward the room; it is cased hi at the sides and front, so that thecurrent can only pass
RM2AFK3TK–. Preventive medicine and hygiene. low fevermosquito. The winged insect may also survive a short winter. Underthe most favorable conditions as to temperature (30° C.) Stegomyiaeggs hatch out in about 36 hours after they are laid. Under 20° C.they will not hatch at all. Larva.—The egg hatches the larva (wiggle-tail), which has ablack barrel-shaped respiratory siphon. This distinguishes it from Culexpipiens, its common mess mate, in which the air tube is brown, longer,and more slender. Although the larva lives in the water, it is strictlyan air-breather and must come to the surface for air. It t
RM2AFJD9P–. Preventive medicine and hygiene. he gas buret. In this case it is advisable to discard thefirst filling of the gas buret A in order to get rid of the air in the rubbertubing and connections. About 4 minutes are required for an analysis.The accuracy is about 1 part in 10,000. The air buret A, which is enclosed in a water jacket 0, consists ofa wide, ungraduated and a very narrow graduated portion. This isdivided into 100 divisions, each of which corresponds to 1 part in 10,000.The lowest division is marked 0 and the numbering is upward from thispoint. Any difference between a reading at or ne
RM2AFHF8F–. Preventive medicine and hygiene. on. At least half anhour should elapse before canteens are filled from the faucets. The British in the present campaign are using a 100-gallon metaltank on two wheels, to which twenty-five grams of hypochlorite areadded. AVater is collected from indicated sources, and allowed to standover night with its charge of bleach. The French water cart is made upof two barrels on a pushcart, or may be horse drawn. The water is alsodisinfected with bleach. In addition both forces analyze the water ofsprings, wells, streams, etc., which are then labeled as potable or non
RM2AFK372–. Preventive medicine and hygiene. mosquitoes convey the infection, the preventivemeasures must be along general lines; a combination of those describedunder malaria and yellow fever, as well as general sanitation and per-sonal hygiene. FLIES The true flies have but two wings, that is, they belong to the orderDiptera. They comprise an enormous number of species. Contrary topopular opinion, flies are poor scavengers. Most flies prefer the sun-shine, but species vary greatlyin their habits and breedingplaces. However, surprisinglylittle is known of the life his-tory and habits of most flies.The
RM2AFJWT1–. Preventive medicine and hygiene. ples and many of the details forthe prevention of plague have been stated in the foregoing pages, andneed not be repeated. Personal prophylaxis consists in avoiding the infected regions andguarding against flea bites. Physicians and nurses should rememberthat the pneumonic form of the disease is highly contagious in theordinary sense of the term. Attendants and persons who come in con-tact with such cases may protect themselves with Haffkines prophylac- 286 INSECT-BOENE DISEASES tic. Individual measures to guard against droplet infection, such as thewearing o
RM2AFKBD9–. Preventive medicine and hygiene. upon theprobability of the take, as well as the protection. It is not wise to de-pend upon one. There is a definite relation between the number ofvesicles and the degree and length of the immunity (see page 17). TheGerman regulations of 1899 require at least four incisions, each one cen- SMALLPOX AND VACCINATION 11 timeter long and two centimeters apart. The Local Government Boardof England directs that four vesicles should be produced, and that thetotal area of the vesicle formation shall not be less than one-half a squareinch. My own practice follows that o
RM2AFHR1W–. Preventive medicine and hygiene. ithstand the pressure. Water is placed in the kettle and the heat is applied to the bottom, usually by means of several Bunsen gas jets. The apparatus is surrounded as high as the shoulder, where the lid is attached, with a metal jacket which serves the purpose of bringing the heat of the flame in contact with the entire surface of the kettle. The lid is made to fit tightly by means of screw bolts and a rubber gasket. A thermometer, pressure gage, safety valve and a small open-ing with a stopcock for the purpose of al-lowing the escape of the air are provided
RM2AFK2MJ–. Preventive medicine and hygiene. matter in the pits and then deposit it and feed upon the food prepared for the soldiers atthe mess tents. In some instances, where lime had recently been sprinkledover the contents of the pits, flies with their feet whitened with lime wereseen walking over the food. Vaughan subsequently stated that he con-sidered that about 15 per cent, of the cases of typhoid in the camps werecaused by fly transmission. Alice Hamilton ^ isolated typhoid bacilli from 5 out of 18 house flies captured in Chicago inthe privies and fence neara sick room. It has beenshown experime
RM2AFJ8PD–. Preventive medicine and hygiene. Fig. 99.—Proper Construction of a Well. ^The word artesian is derived from Artois. an ancient province in Francewhich was supplied with flowing wells. SOUECES OP WATEK 813 shield should join the well casing so as to make a tight joint with the cas-ing. The floor of the well should rest upon the top of the casing, so thatno space is left for frogs, mice, or bugs to crawl in. The floor shouldlikewise be water-tight, and is best made of reinforced concrete with acement surface. If this is not practicable, it should be made of sound,hard, tongue-and-grooved board
RM2AFHK69–. Preventive medicine and hygiene. ade Record. (Physical Examination of Recruits for En-listment in the Navy and Marine Corps, Gov. Printing Office.) After the recruit has been sworn in, his identification records aremade. These records consist of a front and side view photograph, anyindelible marks which appear on his body (scars, moles, etc.), and theprints of all his fingers. These papers are sent on to Washington andare filed there at army headquarters as part of the record of the soldier. 1192 MILITARY HYGIENE Another paper is completed at this time and is called a descriptiveand assignme
RM2AFJWF5–. Preventive medicine and hygiene. ^^ Yonse serum cOiM, ^Sf Oufy/onc/ers CG/onc/e/sOnffaen) + ? D. BS JfoKie serum ^^0 4^i^ff/£fn£/er^ (G:/cinc/er:s +% Comptement:. ^Bacyeno/usis /IJS Fig. 49.—Diagrammatic Representation op Complement Fix-^tion. Mohler andEichorn, Bull. 136. B.A.I., U. S. Dept. of Agriculture. A, Hemolytic system. B, Bacteriolj^ic system. C, Negative reaction with normal horse serum. D, Positive reaction with glandered horse serum. ysis. If the blood serum of the horse to be tested does not containthese specific amboceptors, this fixation of the complement cannottake place and
RM2AFHF58–. Preventive medicine and hygiene. The best design is the Havard latrine box. The seatsare arranged so that thev are always closed save when in use, and are SANITATION OF BAKRACKS AND CAMPS 1285 in pairs, back to back. The box should be lightproof and fly-tight, andshould completely cover the pit, which is ten feet deep by six feet wide;the length depends upon the number of seats. The pit is edged with aboard frame on which the latrine box rests. It is preferable to dig tbcpits in pairs, so that the latrine box can be in use while one of them i.sbeing burnt out. The pit is so deep tbat tbe boa
RM2AFJDTP–. Preventive medicine and hygiene. cerned, but as the thoroughness of the curing is notalways certain, such meat should also be cooked before it is eaten. The trichinae are not particularly resistant, being killed at 155° F.if they are not encapsulated, otherwise at 158° to 160° F.; that is, theyhave about the same resistance as non-sporulating bacteria. Trichina larvae die in 20 days at a temperature not higher than5° F. Eansom ^ di-sproved the notion formerly held that the larvaeof Trichinella spiralis are very resistant to cold. He recommends thatmeat should be refrigerated at a temperature
RM2AFJJ97–. Preventive medicine and hygiene. whether related or not, have only imbecileoffspring. Davenport states that there is no case on record where twoimbecile parents have produced normal children. Dr. H. H. Goddard, of the Training School for Feeble-Minded, atVineland, N. J., has studied the ancestry of children in the Vinelandinstitution and has found almost without exception a history of feeble-mindedness for several generations. Dr. Goddards remarkable study ofthe Kallikak family has already been referred to. In this instance hetraced the ancestry of a 22-year-old girl through about 1,100 indi
RM2AFK2M7–. Preventive medicine and hygiene. FiG. 31.—PuPARiuM OF House Fly. brewers refuse (spent hops), etc.house fly, but have a sharp, needle-like proboscis,sively on mammalian blood and are a great annoyance to horses andcattle in late summer and autumn. They bite persons less frequently,but are of importance onaccount of their possiblerelation to poliomyelitis,anthrax, etc. The sta-ble fly can best be con-trolled by eliminating itsbreeding places. Flies as MechanicalCarriers of Infection.—Leidy in 1864: attributedthe sjDread of gangrenein hospitals during theCivil War to the agencyof the house fly
RM2AFK15N–. Preventive medicine and hygiene. ly. These observa-tions were subsequently verified and extended by Simonds, Offelman,McEae, and others. It is now quite evident that flies lighting upon a case of smallpox,measles, scarlet fever, and other exanthematous disease may very readilytransmit these infections to another person. I have actually seen mag-gots breeding in the open lesions of a case of smallpox treated in theopen air at Eagle Pass, Texas. Flies may, in the same mechanical way, transmit the infection oferysipelas, anthrax, glanders, and other skin infections. It is knownthat flies may in
RM2AFK3RP–. Preventive medicine and hygiene. Fig. 23.—Head of Stegomyia Calopus (male). 340 INSECT-BOENE DISEASES rapidly to the bottom, where, indeed, it may very commonly be observedto feed. The duration of the larval sta^e is never less than 6 to 7. Fig. 24.—Eggs of Stegomyia Calopus. days, and depends upon the food supply and temperature. Under certainunfavorable conditions it may be prolonged for weeks. Freezing for shortperiods does not appear to injure it. Pupa.—The larva changes into the pupa. The pupa is not provided
RM2AFHNAD–. Preventive medicine and hygiene. r disinfection. Fortunately, it isseldom necessary to disinfect such packages. When, however, this iscalled for it is essential to open and properly expose such objects to theaction of the disinfecting agent. In the municipal disinfecting stations of Paris the process of apply-ing steam under pressure is as follows: The pressure is brought up to15 pounds in the chamber and held there five minutes; then released.The pressure is again brought up to 15 pounds, held there five minutes,and again released. This is repeated three times, when the disinfectionis compl
RM2AFJ207–. Preventive medicine and hygiene. urification Processes.—Sub-surface Ireigation.—For small instal-lations a satisfactory method of disposing of sewage after sedimentationis to discharge it through 3-inch or 4-inch tile pipes laid in the ground10 to 18 inches deep in rows 2^/2 to 3 feet apart. In sandy soils thismethod gives satisfaction, and under favorable conditions the sewageof 150 to 250 people can be applied to an acre, the rate of applicationbeing commonly one to two gallons per lineal foot, or 20,000 to 30,000gallons per acre daily. With tight soils larger areas are required.With clay
RM2AFHKPR–. Preventive medicine and hygiene. t in the Navy and Marine Corps, Gov. Printing Office.) As soon as the recruit has passed his physical examination he issworn into the service by the recruiting officer. At the same time ablank, called the physical examination for enlistment, is filled in. Thispaper contains a record of his complete physical examination, and alsoany information in regard to the previous life of the recruit which canbe obtained from him. The enlistment paper, which is made out and signed by the recruit EECEITITS AXD RECRUITING 1191 at the time he is sworn into the service, is p
RM2AFJJR9–. Preventive medicine and hygiene. transmitted directlyfrom parents to offspring less frequently than we have heretofore beenled to believe. Chronic alcoholism in the parents is also regarded as a potent pre-disposing factor in the production of epilepsy. Echeherria has analyzed572 cases bearing upon this point, and divided them into three classes, ofwhich 257 cases could be traced directly to alcohol as the cause, 126cases in which there were associated conditions, such as syphilis andtraumatism, 189 cases in which alcoholism was probably the result ofth€ epilepsy. Figures equally strong are
RM2AFK1K7–. Preventive medicine and hygiene. matter in the pits and then deposit it and feed upon the food prepared for the soldiers atthe mess tents. In some instances, where lime had recently been sprinkledover the contents of the pits, flies with their feet whitened with lime wereseen walking over the food. Vaughan subsequently stated that he con-sidered that about 15 per cent, of the cases of typhoid in the camps werecaused by fly transmission. Alice Hamilton ^ isolated typhoid bacilli from 5 out of 18 house flies captured in Chicago inthe privies and fence neara sick room. It has beenshown experime
RM2AFHGFE–. Preventive medicine and hygiene. al months, but have recurrences from time to time.Such carriers probably spread the disease. Treatment.—Treatment consists mainly of rest and attention to thebowels. Acetjd-salicylic acid is the most effective analgesic drug. Quiningiven by mouth seems to have no obvious effect. Local applications,both hot and cold, are useful for the painful shins. The cases shouldbe isolated and sanitary cleanliness observed. TRENCH FOOT Trench foot was first described by Larrey,^ the distinguished mili-tary surgeon of Napoleons campaigns, and noted later in the Crimeanand
RM2AFJ2A7–. Preventive medicine and hygiene. ge,according to the fineness of the screens. It is pressed and burned undera boiler or buried in land. Screening has attained its greatest develop-ment in Germany. Sedimentation.—Sedimentation is the most important of the pre-paratory processes. By allowing the sewage to flow slowly throughbasins in which the velocity is checked some of the suspended matter isdeposited and the sewage clarified accordingly. There are five typesof sedimentation basins: (1) grit chambers or detritus tanks, (2) plainsettling tanks, (3) septic tanks, (4) digestion tanks, and (5) c
RM2AFJA2N–. Preventive medicine and hygiene. nd pressure, so that deep wells and artesian waters are frequently SOURCES OF WATER 807 unfit for domestic use on account of tlie large amount of inorganicimpurities which they contain, such as lime, iron, common salt, etc. The water that soaks into the soil finally rests upon an imperviousstratum. Such water, as a rule, does not exist in the ground as a river ^or lake, but occupies rather the spaces between the sandy particles, exceptin limestone formations. Ground water, therefore, in any quantity isfound, as a rule, in sandy, gravelly, or sandstone formati
RM2AFK92G–. Preventive medicine and hygiene. Eighth Day Ninth Day Fig. 3.—Vaccinia. Course of the Eruption from the Fourth to the Ninth Day. 14. Fourteenth Day Scar—Sixth Week Fig. 4.—Vaccinia. Course of the Eruption from the Tenth Day. 15 16 DISEASES HAVIXG SPECIAL PROPHYLAXIS it is also exceptional to have smallpox occur in an individuar who hasbeen properly vaccinated. SMALLPOX In Liverpool during ten years 0902-1911), verity of the dlweaee ao it affects vaccinated and iThU DlfL-^nun ie bft&ed on (h« reoords of 1193 CAMS of ftmaJUpox. ed peroonci. PERSONS VAOOINATED IN INFANCY.
RM2AFHF0T–. Preventive medicine and hygiene. the men astride. It is easily and quickly made,and by reason of its slight depth permits more rapid disintegration ofthe excreta and is easily filled on breaking camp. Accommodationsshould be provided for 5 per cent of the command. A cover for the straddle pit, devised by Major R. U. Patterson, ofthe United States Army, is shown in Fig. 200. It is arranged for two.The lid for each opening falls unless held open. This cover onlyrequires a little lumber and four strap hinges.. Fig. 202.—Pit for Kitchen Refuse. (Wilsons Field Sanitation, George Banta Pub. Co.) A
RM2AFJEB8–. Preventive medicine and hygiene. C... Fig. 75.—Straus Home Pasteuuizer, Freemans pasteurizer for heating milk in individual feeding bottlesin the home is most serviceable. The modification of Mr. Nathan Strausis shown in Fig. 75. It is used as follows: After the bottles have been thoroughly cleaned they are placed inthe tray (A) and filled with the milk or mixture used for one feeding.Then put on the corks or patented stoppers without fastening themtightly. The pot (B) is now placed on the wooden surface of the table orfloor and filled to the supports (C) with boiling water. Place the tray(A
RM2AFJRFT–. Preventive medicine and hygiene. Fig. 54.—Third Stage.THE Receptors Begin-ning to Leave theCell. effects. ^Ehrlich, P.. i: Morgenroth. J.: Wirkung und. Entstehimg der aktiven Stoffeim Serum nacli der Seitenkettentheorie. Handbuch. der pathogenen Mikroorgan-ismen,, W. Kolle, and A. Wassermann, Jena, 1904. 413 IMMUNITY. Fig. 55.—ForRTH Stage:THE Receptors HaveLeft the Cell andFloat Free ix theBlood—Antitoxin. The connective tissue is believed to be specially rich in receptors,evidenced bj tbe local reaction caused by the subcutaneous inoculation ofdiphtheria toxine, ricin, abrin, and similar p
RM2AFJ71F–. Preventive medicine and hygiene. After a person becomes accustomed to the taste of a par-ticular water another does not appeal to him and does not satisfy histhirst to so great an extent. Once having been accustomed to a moder-ately hard water, a soft water is very flat and tastes much like distilledor rain water. Odors in waters are objectionable, rather than detrimental to health.As a rule, the most objectionable odors develop in surface waters andare caused by the growth of algae, diatoms, protozoa, and other micro-scopic beings. The earthy odor of some ground waters is due to sub-stances
RM2AFHMDC–. Preventive medicine and hygiene. disinfect-ing the holds of vessels the pipe is usually let down the hatchway untilit is near the bilge. The heavy gas collects at the bottom and graduallyascends, displacing the air, so that it is important to allow an opening GASEOUS DISINFECTANTS—FUMIGATION 1143 of some sort for the exit of the air near the top of the compartment thatis being disinfected. This opening should not he closed until the gasescapes freely. The KinyourirFrancis furnace consists of an iron pan upon whichthe sulphur is burned. Under this pan is a firebox with ashpit and nec-essary d
RM2AFK60Y–. Preventive medicine and hygiene. typhoid bacillus is much more widely dis-tributed in man than the cases indicate. Thus, in the District ofColumbia, of 1,000 healthy persons examined during the typhoid seasonof 1908, typhoid bacilli were found in the feces in 3 instances. At leastone and perhaps two of these individuals were regarded as temporarycarriers. In each instance the organisms were found only once. Thepopulation of the District of Columbia in 1908 was 300,000, and at theratio of 1 per 1,000 this would represent about 300 healthy persons inthat community harboring and shedding typhoi
![. Preventive medicine and hygiene. or one division during one year. Trench fever has been reported especially in Flanders, France, andEngland, but also from the troops in ]Iesopotamia, the Balkans, Salonica, 1 Hunt, G. H., and Rankin, A. C.: Intermittent Fever of Obscure Origin. Oc-curring Among British Soldiers in France, The Lancet, Nov. 20, 1915, p. 1133. DISEASES OF THE SOLDIER 1245 on the Volhynian front, and among Austrian and German troops onthe eastern front, and in Austrian troops in the Tyrol, Definition.—Trench fever includes a great number of cases of con-tinued, intermittent, irr Stock Photo](https://c8.alamy.com/comp/2AFHHM1/preventive-medicine-and-hygiene-or-one-division-during-one-year-trench-fever-has-been-reported-especially-in-flanders-france-andengland-but-also-from-the-troops-in-iesopotamia-the-balkans-salonica-1-hunt-g-h-and-rankin-a-c-intermittent-fever-of-obscure-origin-oc-curring-among-british-soldiers-in-france-the-lancet-nov-20-1915-p-1133-diseases-of-the-soldier-1245-on-the-volhynian-front-and-among-austrian-and-german-troops-onthe-eastern-front-and-in-austrian-troops-in-the-tyrol-definitiontrench-fever-includes-a-great-number-of-cases-of-con-tinued-intermittent-irr-2AFHHM1.jpg ". Preventive medicine and hygiene. or one division during one year. Trench fever has been reported especially in Flanders, France, andEngland, but also from the troops in ]Iesopotamia, the Balkans, Salonica, 1 Hunt, G. H., and Rankin, A. C.: Intermittent Fever of Obscure Origin. Oc-curring Among British Soldiers in France, The Lancet, Nov. 20, 1915, p. 1133. DISEASES OF THE SOLDIER 1245 on the Volhynian front, and among Austrian and German troops onthe eastern front, and in Austrian troops in the Tyrol, Definition.—Trench fever includes a great number of cases of con-tinued, intermittent, irr Stock Photo")
RM2AFHHM1–. Preventive medicine and hygiene. or one division during one year. Trench fever has been reported especially in Flanders, France, andEngland, but also from the troops in ]Iesopotamia, the Balkans, Salonica, 1 Hunt, G. H., and Rankin, A. C.: Intermittent Fever of Obscure Origin. Oc-curring Among British Soldiers in France, The Lancet, Nov. 20, 1915, p. 1133. DISEASES OF THE SOLDIER 1245 on the Volhynian front, and among Austrian and German troops onthe eastern front, and in Austrian troops in the Tyrol, Definition.—Trench fever includes a great number of cases of con-tinued, intermittent, irr
RM2AFK7T4–. Preventive medicine and hygiene. ared; (2) they may run a somewhatmore rapid course in which the period of incubation is shortened andin- which the height of the pustular stage occurs about the sixth day(this is known as the accelerated reaction); or (3) they may run avery much shortened, milder, and rapid course. The eruption may beonly a small papule which does not develop into a vesicle and soon dis-appears; the period of incubation may be less than 24 hours. This isknown as the immediate reaction and resembles a cutaneous tuberculinreaction in many respects. These altered reactions have
RM2AFJ9WN–. Preventive medicine and hygiene. us rock,for limestone is not porous. The water travels through fissures or pas-sages. T^Hien these are large they are called caverns or cavea, as, forexample, the Mammoth Cave in Kentucky. These caverns or caves arenatural seams or cracks enlarged by the gradual solution and removalof the limestone by the passing water. Limestone is the only commonrock that is soluble in this way, and, for water supply purposes, lime-stone formations must be distinguished from all others. The crevices may be, and often are, continuous for many miles.They are remarkably tortuo
RM2AFJMWA–. Preventive medicine and hygiene. Fig. 65.—Model to Illustrate the Law of Probability or Chance. A, Peasheld in container at top of board. B, Peas after having fallen through the obstruc-tions into the vertical compartments below. The curve connecting the tops of thecolumns of peas is the normal probability curve. ideas and without neglecting any members. In this respect statisticalmethods differ from biological methods, which require careful discrimi-nation of data. The quantitative determination of a character may be made by variousmethods, as by counting or by measurement. The statistical
RM2AFHGPF–. Preventive medicine and hygiene. y incriminate an enterocoecus, a normal inhabitant of the intes- 1 MacGregor, R. D.: A Case of Trench Fever Contracted in England, Brit-ish Medical Journal, Feb. 17, 1917, p. 221.41 1248 MILITAEY HYGIENE tinal tract of man, and found in numerous disease states, both medicaland surgical.^ It has also been pointed out that as many of the men have been hitwhile using the latrines, there is a decided tendency to go for three orfour days, or longer, without a bowel movement. One group of thesepyrexias may perhaps be ascribed to this cause, since corrective measure
RM2AFJXFP–. Preventive medicine and hygiene. Fig. 40.—The Indian Rat Flea {Xenopsylla cheopis Rothsc.)} Then they spin flat, white, silken cocoons in which they transform tothe pupal stage. In from 5 to 8 days the adult flea emerges from thecocoon. The period of their transformation is affected by the tempera-ture and moisture. In warm, damp weather a generation may developin ten days or two weeks, but usually about 18 days to three weeks
RM2AFJ9EF–. Preventive medicine and hygiene. dais still supplied large-ly from this source.Paris in France ispartially supplied withlimestone Avater. A^i-enna obtains its sup-ply from the wonder-ful Kaiserbrunnenand other limestonesources, which are allin the high mountains,where there is scarcelyany population or pol-lution. This sui^ply is mainly from the melting ice and snow of the highmountains which replenishes the springs, so that the amount of waterobtainable is greater in summer than winter. Typhoid fever has been caused rather frequently by the use of groundwater from limestone formations. This
RM2AFJKDH–. Preventive medicine and hygiene. of its occurrence in manymembers of the same family. Thus, out of 104 cases of diabetes mellitus22 had a family taint—about 20 per cent. Xaunyn obtained a history ofdiabetes in 35 out of 201 private cases, but in only 7 of 157 hospitalcases. Orthostatic Albuminuria.—Orthostatic albuminuria occurs in boysmore commonly than girls. These are often the children of neuroticparents, and have well-marked vasomotor instability. Defects or pe-culiarities in the filtering apparatus in the kidneys may arise as agerminal variation and be handed on from generation to gene
RM2AFK3HH–. Preventive medicine and hygiene. Fig. 24.—Eggs of Stegomyia Calopus. days, and depends upon the food supply and temperature. Under certainunfavorable conditions it may be prolonged for weeks. Freezing for shortperiods does not appear to injure it. Pupa.—The larva changes into the pupa. The pupa is not provided. Fig. 25.—Larva of Stegomyia Calopus.Respiratory Syphon of Culex to the Right. MOSQUITOES 241 with a mouth and does not feed. It is an air-breather and spends mostof its time at the surface of the water. The pupal stage lasts at least3G hours, during which time metamorphosis occurs int
RM2AFJP5K–. Preventive medicine and hygiene. produce aprogeny sorting into three classes, and in the same proportion as thatproduced by the blues of the original hybrid generation. The fact thatthe black grandchildren and the white grandchildren respectively breedtrue is a very important fact. In this illustration no race of the hybridblue character can be established, for the blues always produce blacksand whites as well as blues (see diagram). Another instance which illustrates the phenomenon of dominant andrecessive characters as well as segregation is here given. If black andwhite varieties of guine
RM2AFJC0D–. Preventive medicine and hygiene. n ahayloft were smitten. It is estimated that a person living in London breathes about 300,-000 microbes in the inspired air each day. The expired air, during normal respiTations, is practically bacteria-free, no matter how many may be contained in the inspired air. Themoist mucous membranes of the upper respiratory passages act as abacterial trap. When the expired air contains bacteria it is only as aresult of coughing, sneezing, talking, or other forced expiratory efforts(see Droplet Infection). The harmful bacteria in the air and the danger of contracting
RM2AFJC5P–. Preventive medicine and hygiene. losingthe upper end of the glass tube isfitted with two lateral tubes of hardrubber h and c, and also carries a delicate themometer, the bulb of whichis placed near the center of the silver tube. The tube h extends to thebottom of the silver tube; c projects but a short distance through thecork. A rubber aspirating apparatus, as shown, is connected with thetube h, and a long tube joined to c serves to carry off the fumes. Theapparatus is held in a clamp faced with cork or other non-conductingsubstance. Observations are made by filling the silver cup with ethe
RM2AFJWX7–. Preventive medicine and hygiene. FiG. 43.—A Squirrel Flea (Hoplopsyllus anomalus Baker.). tance of these discoveries, it is only necessary to call to mind that, inorder to eradicate plague forever from the surface of the globe, a war-fare against the rat alone is not sufficient, but must include the rodentsmentioned and perhaps others. Simond in 1897 advanced the theory that plague was carried byfleas. This theory was developed by J. Ashburton Thompson and othersand conclusively proved by the Indian Plague Commission. The exactmethod by which the flea transmits the infection from animal to a