528 FOOD PRESERVATION 
suggested as a factory-working basis in 1911, represents at least 0.8 to 
0.9 per cent of rot. There may be more rot than that present, but, on 
the basis of the data at hand, it is highly improbable that it represents 
less than that amount. From the chart it is possible to calculate the 
approximate minimum percentage of decay represented by a given mold 
count. Thus, for instance, a mold count of forty enters the ‘ Zone of 
Permissible Mold Counts’ at a point representing 2.2 per cent of 
decay. Therefore, a count of forty may be obtained in samples having 
any amount of rot between 2.2 and 100 per cent.” 
Vincent’s Method for the Examination of Tomato Paste. Vincent 
(1918) has attempted to overcome the errors of the Howard method by 
adapting the Breed smear to tomato products. The method 1s described 
as follows: ‘‘ The catsup is diluted with two parts of sterile water, since 
this dilution has proven satisfactory in counting most specimens when 
the Zeiss counting chamber is used. With a sterile pipette calibrated 
to deliver 0.01 ¢.c. the diluted catsup is deposited on a second glass slide 
and evenly spread over an area of 1 sq. cm. by means of a sterile needle. 
After drying, the slide is immersed in 95 per cent alcohol for one minute 
to fix the smear, dried in air, stained with Loeffler’s methylene blue 
for two minutes, washed in water, dried and examined with the 1/12 in. 
oil immersion lens.’”’ The rest of the procedure is identical with that 
outlined under Breed’s microscopic method for counting bacteria in 
milk. The microscope is standardized to bring the diameter of the field 
to 0.205 mm. Thirty fields are counted and the average for one field 
is multiplied by three on account of the dilution of the catsup. This 
result is then multiplied by 300,000, which represents the number of 
bacteria per cubic centimeter. 
Vincent compared this microscopic count with the count secured 
with the Zeiss blood counter. The latter count was always much 
greater than the former. Vincent believes that the cocci should 
be counted since they probably take as important a part in the spoilage 
of tomatoes as the rods, 
Foop PorsoninG 
In the past, this term has covered a multitude of physiological 
disturbances in the alimentary tract. For some, it has been a very 
easy matter in the past to diagnose an ailment as food poisoning 
or ptomaine poisoning when other possibilities have been excluded. 
The term “ ptomaine poisoning’ was used by many for a time, but 
this is gradually being discarded for terms with more meaning. More 
