The Minneapolis journal. [volume] (Minneapolis, Minn.) 1888-1939, 1903-09-23
GERMS TURN UP TOES
Psychologists Make Practical Tests
Of Electricity as Water
Purifier.
The Process Proves More Effective
Than Any Other Known
Method.

Figures which have been furnished by
Professor George d. Shepardson and City
Bacteriologist j. Frank Corbett, who have
recently conducted another test of the
Johnson process for purifying the city
water throw new light on the invention
and Indicate that its use would be not
only great protection to the users Of
city water but also much cheaper meth
cd than the use of sedimentation basins
or any other process of purifying the
water.
Several tests of the Johnson process
into which the use of electricity enters
| largely, have been made by DR.. Corbett
and others and the fact that it does al
most eXterminate the bacteria in the
water has been demonstrated more than
once; but, up to the time this report was
made, the practicability of the process
was not determined because the cost Of
using 1t had not been made certainty.
This last report shows that while the
water from the pipes in the east side
pumping station-where the water is the
most unprecedented, normally, 6S2
bacteria per cubic centimeter before
treatment, there remained but Sc bac-
terra per cubic centimeter after treat
ment, thus eliminating at least 80 per
cent OF the bacteria, higher percentage
than that credited to any other process.
The reports show that the electricity
passed thru the water would cost at usual
! rates something less than 81 per 100000
gallons treated. But even this low figure
can be reduced in the opinion Of the in
| ventor, when plan for the purifying of
all the city water is installed at the reser-
voir, or in the mains leading from the
Camden place or Northeast pumping sta
ton. Mr.. johnson plans to generate the
| electricity used in the process by putting
turbine wheels in the pumping house
mains or at the outlet to the reservoir,
thus reducing the cost Of the electricity.
| Four tests were made by Professor
Shepardson, the water in each case pass
ing thru the apparatus at the rate of 19
| cubic feet per minute which was eQuiva-
lent to S,527 gallons per hour. In test A.
and B. $50 volts were used; in test G the
voltage was $50 ad in test D, 10. Assam
ing that electrical power costs $40 per
kilowatt hour the cost for electricity in
these tests would be SLIT, $40, s27.40 and
$.97 per million gallons, respectively, the
difference In the cost of the A and tests
being caused by the Indifferent manner
of applying the electric current.
| IN his report Dr. Corbett says: "The
results show that your apparatus is as ef-
fective with ITO volts, the lowest pres.
sure tried, as with $50 volts. The prob.
ability is that still lower voltage might
be practically as effective, resulting ir
lower cost of treatment
Professor Shepardson says in his report
"The amount of electrical energy re.
CURED can probably be reduced still fur.
Their by subsequent development of the
apparatus. see no reason to anticipate
any electrolNtic action upon the water
pipes from the use of your system of puri.
fication when properly designed, installed
and operated
Joseph Johnson, the inventor of thu
process, has been working on it for three
years. He IS employed at the Camde,
Place pumping station and lives at 32l
Twenty fourth avenue where most o.
the details have been worked out.