It seems probable that the Germans in Italy are using all available Italian
equipment. An account of a particular Italian smoke
pot candela fumogena 2-Kg (4.4 lb) thus
appears to be timely.
a. Physical Characteristics
(1) This candela fumogena is shown in figure 1. It consists of a 30-gauge
tin-plate can (2) 3 inches in diameter and 10 inches high, with a 9/16-inch recess
at the top which houses the igniter pellet and striker pad during shipment, and is
closed by a lid sealed on with adhesive tape. The bottom of the candle has a zinc
well, 3/4-inch diameter and 1 3/4 inches deep, into which the igniter pellet is
inserted for firing. The candle is painted dark green and has a label with the
marking F/ZN and instructions, (for use), translated as follows:
|
Italian 2-Kg Smoke Pot |
(a) Pull off the tape, take off the cover, and take the striker and igniting cartridge from the receptacle.
(b) Place the igniting cartridge in the zinc tube in the bottom part of the candle.
(c) Ignite by rubbing the striker on the matchhead.
(d) Place the candle lying down on the ground.
(e) Get away, preferably up wind.
(f) When the igniter does not set it off, try another.
NOTICE: The candle should be kept in a dry place.
Figure 1 (the smoke pot) shows the compartment in which the ignition
element is shipped; the candle (2) shows the recess for the ignition element (6) - the
latter consisting of a scratcher pad (4) with waxed wrapper (5) and cover (3). The
match head, of the Bickford type fuze and starter pellet is wrapped in a waxed
paper wrapper with a waxed paper sleeve (7).
(2) In a smoke pot which has been examined, the candle weighed 2.27 kilograms (5 lb) and
contained 2.03 kg (4.47 lb) of the following Berger-type smoke elements:
Zinc Chloride (water soluble zinc) | | 0.80% |
Zinc Oxide | | 21.07% |
Zinc Dust (total zinc minus zinc chloride and zinc oxide) | | 25.83% |
Kieselguhr (hydrochloric acid insoluble) | | 12.03% |
Carbon Tetrachloride (by difference) | | 40.27% |
(3) The igniter element weighed 10 grams (.35 oz) and consisted of a
matchhead of the antimony sulfide-potassium chlorate type, a 1-inch length of
Bickford type safety fuze, and a starter pellet 11/16 inches in diameter and 1 inch
long, of the following composition:
Potassium Nitrate | | 55% |
Calcium Silicide | | 45% |
The calcium silicide consisted of approximately 31% calcium, 64% silicon and 5% iron.
(4) The scratcher pad was made of 1/16-inch cardboard, 5/8 inch by 1 3/8 inch, and sensitized on one side.
(5) Inside the can, on the bottom, were two cardboard disks, 2 and 13/16 inches
in diameter, and 1/16 inch thick. The disks were probably used for insulating
the bottom of the can in case the starter element was accidentally ignited.
b. Functional Characteristics
One candela fumogena was tested for functioning in comparison with the
HC smoke pot, M1 (see figure 2). The Bickford type safety fuze in
the candela fumogena gave a delay of 2 to 3 seconds. The burning time was 1 minute, 15 seconds. For
the first 15 seconds the smoke from the Italian smoke pot was whiter than
the smoke from the M1 smoke pot, after which the color was about the same. The
smoke from the candela fumogena pillared much more than that from
the M1 smoke pot. The volume of smoke, per unit time, was about equal for each smoke pot.
|
American M1 (Left) and Italian 2-Kg Smoke Pot (Right) |
c. Comparison With Similar U.S. Equipment
The Italian smoke pot is comparable to the HC smoke pot M1. The candela fumogena
weighs 5 pounds gross and burns for 1 1/4 minutes. The M1 smoke pot
has a gross weight of 11 pounds and burns for 6 1/2 minutes (burning time varies
between 5 and 8 minutes). Since both smoke pots gave approximately the same
volume of smoke per unit time, the Italian smoke pot had only 45% the gross
weight efficiency of the comparable M1 smoke pot.
The assembly of the M1 smoke pot is considered superior to the Italian
since the ignition element in the base of the Italian pot is an extra part to be
misplaced, but gives no added advantage. The need for the delay furnished by the
Bickford type safety fuze on the Italian pot is not apparent, except that occasional
scattering of burning material might endanger personnel.