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The indicator may be prepared as follows: .
Brom thymol blue.------------------------------ 0.1 gram.
N/20 NaOH........

------ 3.2 c. c. Grind in agate mortar. When solution is complete, add 3 c. c. of distilled water.

Due to the fact that a great number of the pathogenic and allied organisms grow best near pH 7.2 or 7.4, it was found that the necessity for adjustment of the medium could be eliminated by the addition of the proper amounts of disodium hydrogen phosphate and monopotassium hydrogen phosphate. The following formula will produce (a medium varying from pH 7.2 to 7.4, depending upon the nature of the ingredients used: Tap (or distilled) water....

1,800.0 c. c. Peptone.

10.0 grams. Na,HPO,-.

14.5 grams. KH,PO,

1.4 grams. Agar .--.-.

- 2.0 grams. The salts and peptone tend to stabilize the medium, but the buffer strength is not sufficient to prevent appreciable change in the hydrogen ion concentration resulting from attack of the fermentable substance. If a higher or lower pH value is desired, the salts can be varied according to Sørensen's table.

As control on the growth of the organism in this medium without the addition of fermentable substances, it is necessary to prepare one lot of tubes without such substances; that is, using merely the water, peptone, potassium and sodium salts, agar, and indicator. In case attack is made upon the peptone which might be considered as obscuring the results of the carbohydrate attack, this will be indicated in these tubes, which we have termed "nonfermentable controls.”

The following organisms have been grown on this medium with characteristic results:

Bacterium dysenteriæ (all types) Bacterium typhosum, Bacterium paratyphosum Alpha and Beta, Bacterium coli, Bacterium typhimurium; Brucella melitensis, Streptococcus hemolyticus, Streptococcus viridans, Diplococcus pneumoniæ; Corynebacterium diphtheriæ; Neisseria gonorrhea, Neisseria catarrhalis, Neisseria intracellularis meningitidis; Pasteurella pestis; Proteus vulgaris; Vibrio cholera asiaticæ; Clostridium tetani.

The fermentable substances tested were: Erythrose, arabinose, xylose, dextrose, galactose, mannose, levulose, lactose, maltose,

? This table may be consulted in "The determination of hydrogen ions,” by William Mansfield Clark, 2d ed., 1922, p. 114.

saccharose, raffinose; salicin, dextrin, glycogen, starch, inulin, glycerol, mannitol, dulcitol, adonitol.

In case of the aerobes, the inoculations were made with a platinum loop, floating off the inoculum on the surface of the medium. The anaerobes were transferred by placing the inoculum as near the bottom of the tube as possible. Rapidly growing organisms (inoculation having been made from young cultures) show sufficient acid and gas production to be read within 1 to 4 hours after transplanting.

The points in favor of this medium are: Ease of preparation and economy; its known nonfermentable base; clarity; certainty as to growth, which occurs in most cases in featherylike masses as in the Hitchens medium; its ability to support growth of a large number of microorganisms either with or without the addition of carbohydrate or other fermentable substance.

It is believed, from the experiments with this medium, that by its use many of the contradictory results as to acid formation obtained by different investigators will be explained. That is, in many cases, no doubt, broths not actually sugar-free were used, impure sugars were employed, or the sugars were broken down by the heat applied under pressure, or for too long a time.

SUMMARY

A medium has been devised containing a sugar-free base, to which fermentable substances and the indicator brom thymol blue may be added, which serves for fermentation studies on a large number of bacterial species. The medium is based upon the low-percentage agar medium of Hitchens, substituting a synthetic, sugar-free base for the beef broth used by him.

The medium is easily prepared, and very economical, making its use advantageous for testing the purity of large numbers of stock cultures or for classroom demonstration. Actual growth of the organisms under test is readily observed because of the clarity of the medium; and the medium will support the growth of a large number of microorganisms either with or without the addition of carbohydrate or other fermentable substance. Anaerobes as well as aerobes may be studied in this medium. Variations of the salt content might prove advantageous in case of certain species.

: DEATHS DURING WEEK ENDED SEPTEMBER 1, 1923.

welke kendedes Senecen

Summary of information received by telegraph from industrial insurance companies for week ended September 1, 1923, and corresponding week of 1922. (From the Weekly Health Inder, September 5, 1923, issued by the Bureau of the Census, Department of Commerce.)

Week ended Corresponding

Sept. 1, 1923. week, 1922. Policies in force...

. 54, 559, 35250, 486, 420 Number of death claims......

8, 232

7,077 Death claims per 1,000 policies in force, annual rate......

7.9

7.3

Deaths from all causes in certain large cities of the United States during the week ended

September 1, 1923, infant mortality, annual death rate, and comparison with corresponding week of 1922. (From the Weekly Health Index, September 5, 1923, issued by the Bureau of the Census, Department of Commerce).

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Total

5,891 10.7 10.2 896 882 Albany, N. Y.....

16.4 12.6 Atlanta, Ga....

63 14.7 -15.4 Baltimore, Md...

169

11.3 Birmingham, Ala.

13.6 13.9 Boston, Mass....

12.0 12.6 Bridgeport, Conn..

7.3 Buffalo, N. Y.....

111 Cambridge, Mass...

19 Camden, N. J....

11.3

14.5 Chicago, Ill.....

506 9.1

9.3 Cincinnati, Ohio.

104

13.3 14.8 Cleveland, Ohio 3.

162
9.5

7.6 Columbus, Ohio..

13.4 11.7 Dallas, Tex....

10.6 11.2 Dayton, Ohio..

10.7

9.3 Denver, Colo..

12.8 10.9 Des Moines, Iowa.

32 11.8 Detroit, Mich.

11.0 Duluth, Minn..

6.9 Erie, Pa...

8.3 Fall River, Mass..

12.1 Flint, Mich... Fort Worth, Tex.

9.4 Grand Rapids, Mich Houston, Tex.....

13.9 Indianapolis, Ind..

14.0 Kansas City, Kans.

10.4 16.5 Kansas City, Mo..

10.4 13.0 Los Angeles, Calif..

14.0 14.5 Louisville, Ky....

14.2 10.8 Lowell, Mass........ Lynn, Mass........

9.1 Memphis, Tenn....

18.4 17.4 Milwaukee, Wis....

7.9 8.2 Minneapolis, Minn.

8.5

8.3 Nashville, Tenn....

19.8 14.3 New Bediord, Mass.

12.3 New Haven, Conn...

7.2 New Orleans, La.....

131

14.1 New York, NY

1,089 9.6

8.8 Bronx borough.....

126 7.8 Brooklyn borough.

330 8.0

8.1 Manhaitan borough.

525 12.1 10.2 Queens borough...

8.6

7.6 Richmond borough......

9.6 1 Annual rate per 1,000 population.

: Deaths under 1 year per 1,000 births-an annual rate based on deaths under 1 year for the week and estimated births for 1922. Cities left blank are not in the registration area for births. Deaths for week ended Friday, Aug. 31, 1923.

591610-234-2

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Deaths from all causes in certain large cities of the United States during the week ended

September 1, 1923, infant mortality, annual death rate, and comparison with cortesponding week of 1922. (From the Weekly Health Inder, September 5, 1923, issued by the Bureau of the Census, Department of Commerce)—Continued.

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PREVALENCE OF DISEASE.

No health department, State or local, can effectively prevent or control disease without

knowledge of when, where, and under what conditions cases are occurring.

UNITED STATES.

CURRENT STATE SUMMARIES.

These reports are preliminary and the figures are subject to change when later returns are roceived by the State health oflicers.

Reports for Week Ended Sept. 8, 1923.

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ALABAMA.

CALIFORNIA.
Cases.

Cases. Chicken pox.

11 Cerebrospinal meningitis–Los Angeles........ Dengue..

Diphtheria .......

... 129 Diphtheria..

Influenza..... Dysentery....

Measles.......

..... 159 Influenza.....

Poliomyelitis: Malaria.....

344 Los Angeles..... Measles....

Los Angeles County ................ Pellagra.....

24 Scarlet sever................................... Pneumonia...

Smallpox................................. Scarlet fever...

Typhoid fever.. Tuberculosis....

COLORADO. Typhoid fever.........

(Exclusive of Denve Whooping cough.............

Cerebrospinal meningitis........

Chicken pox....
ARIZONA.

Diphtheria....
Chicken pox.............

Measles...... Scarlet fever.....

Mumps...... Tuberculosis.....

Pneumonia... Typhoid lever....

Scarlet fever...

Tuberculosis...
ARKANSAS.

Typhoid fever..........
Chicken pox.........

18 Whooping cough......... Diphtheria.......

CONNECTICUT. Hookworm disease............

| Chicken pox...... Influenza......

18 Diphtheria........... Malaria....................................... 585 Dysentery (bacillary)............. Measles.....

Malaria.............. Mumps..............

1 Measles.......... Ophthalmia neonatorum.

Pneumonia (lobar)..... Paratyphoid fever............

Poliomyelitis...... Pellagra.....

Scarlet fever.... Scarlet fever.

Septic sore throat. Smallpox.....

Smallpox....... Trachoma....

Tetanus..... Tuberculosis....

23 Tuberculosis (all forms)............... Typhoid fever....

8 Typhoid fever................................. Whooping cough............

Whooping cough...

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