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the steam has penetrated everywhere. In the Lyon's machines the
air is withdrawn prior to the admission of steam by the production
of a vacuum.
Drying is effected by allowing the exhaust valve to remain open
and turning steam into a ring between the inner and outer casings.
This forms a steam jacket which evaporates all moisture contained
in the treated articles-a process assisted by the admission of air from a
valve at the bottom of the chamber, while a small ejector in the exhaust-
pipe keeps up circulation.
The action of the machine constructed by Messrs. Richardson &
Cruddas is somewhat different. Its working was tested by Mr. Hewett,
the Assistant Executive Engineer, Municipal Workshops, who reported
that the means taken to get rid of the contained air in the chamber and
to secure a thorough penetration are as follows:-" On the admission of
steam from the outer to the inner casing, or, in other words, from the
boiler to the disinfecting chamber, the pressure in the latter rises to 6lbs.,
corresponding to a temperature 230° F. When this pressure is attained,
a safety valve in communication with the chamber and loaded to 6lbs.
comes into action, and allows all surplus steam to blow off into the
atmosphere. As the boiler continues to generate steam, a current of
steam at the above pressure is continuously passing through the chamber.
This action appears to secure thorough penetration of all articles, for on
wrapping my handkerchief tightly up inside a blanket, and afterwards
withdrawing it from the chamber before the drying operation was
commenced, it was found to be quite damp and hot. In regard to the
drying of the articles after treatment, I find that the apparatus is
as quick, if not quicker, in action than the equifex disinfector. This is
attributed to the fact that, although the steam pressure used is very much
less than in the equifex apparatus, the heating surface is much greater,
and the few clothes treated in my presence were found to be practically
dry after five minutes treatment."
The cost of working this disinfector is somewhat smaller than that
for the equifex, and is estimated to be Rs. 200 per mensem. Its prime
cost is about Rs. 2,000, something less than one-third the cost of an
equifex.