nd determine their identity on the lines laid
down in the previous method.

(B) Parietti's Method:

1. Take nine tubes of Parietti's bouillon (_vide_ page
202)--i. e., three each of those containing 0.1 c.c., 0.2
c.c., and 0.5 c.c. of Parietti's solution respectively.
Mark plainly on the outside of each tube the quantity of
Parietti's solution it contains.

2. To each tube add a different amount of the original
water, or of the suspension, and incubate at 37 deg. C.

3. Examine the culture tubes after twenty-four and
forty-eight hours' incubation, and plate in nutrient
carbolised or potato gelatine from such as have grown.

4. Pick off suspicious colonies, if any such appear on the
plates, subcultivate them upon the various media, and
identify them.

(C) Elsner's Method: This method simply consists in
substituting Elsner's potato gelatine (_vide_ page 204) for
ordinary nutrient gelatine in any of the previously
mentioned methods.

(D) Cambier's Candle Method:

Treat a large volume of the water sample by the
concentration method (_vide_ page 434).

1. Remove the rubber stopper from the mouth of the filter
candle, introduce 10 c.c. sterile bouillon into its
interior, and emulsify the bacterial sediment; replug the
mouth of the candle with a wad of sterile cotton-wool.

2. Remove the filter candle from the filter flask and insert
it into the mouth of a flask or a glass cylinder containing
sterile bouillon sufficient to reach nearly up to the rubber
washer on the candle.

3. Incubate for twenty-four to thirty-six hours at 37 deg. C.

4. From the now turbid bouillon in the glass cylinder pour
gelatine plates and incubate at 20 deg. C.

5. Subcultivate and identify any suspicious colonies that
appear.

(The method depends upon the assumption that members of the
typhoid and coli groups find their way through the porcelain
filter from the interior to the surrounding bouillon at a
quicker rate than the associated bacteria.)

B. ~Enteritidis Sporogenes.~--

1. Transfer 5 c.c. of the emulsion from the filter candle to a sterile
test-tube and plug carefully.

2. Place the test-tube in the interior of the benzole bath employed in
separating out spore-bearing organisms (_vide_ page 257), and expose to
a temperature