Here follows a description of the significant changes made to the
experiment write-up between the first and final drafts. From the final
draft there is a link to the 1st draft, should you wish to see it.
Jay J. Krull
(alias jjk@dnaco.net)
Kettering, Ohio
* * * * * * * * * *
TITLE - No change
BACKGROUND - No change
PREJUDICE OF THE EXPERIMENTER - No change
EQUIPMENT -
* Note that the wooden test tube rack will be placed outdoors, as
opposed to hanging in a window inside.
* Change "test tube clamps" to "plasic or latex gloves."
* Drop "1 pair, long tweezers." Add "thermometer" and "eye dropper."
* Changed "ten (10) each, bean seeds and pea seeds" to
- 1 oz. package of Northrop King brand "Improved Tendergreen
Bean" seeds, identified with stock #7089 and the words,
"PACKED FOR 1999 LOT 5."
- 1.25 oz. package of Northrop King brand "Sugar Ann Pea"
seeds, identified with stock #7501 and the words, "PACKED
FOR 1999 LOT 2."
* In the item "distilled water, in a squirt bottle," drop "in a squirt
bottle." (I've misplaced the one I had. Used an eye dropper
instead).
* Drop "denatured alcohol," "cotton swabs" and "petroleum jelly."
* Change "brown sticky carton tape, 3M brand" to "masking tape,
1.5inch wide."
* Change "grease or wax pencil" with "permanent-ink marker." The wax
pencil mark was easily wiped off the test tube, so I switched to a
marker.
PREPARATION -
There are numerous changes made to the numbered steps for the
preparation of the test tubes.
* Change item 3 to read, "place one bean seed in the test tube on top
of the cotton;"
* Add two new items after item 3:
- "using the eye dropper squirt enough distilled water into
the test tube to saturate the cotton;" and
- "remove from the roll of cotton another wad approximately
1cm by 3cm and stuff it into the test tube so that it covers
the seed;"
* Change item 4 to read, "using the eye dropper squirt enough
distilled water to saturate the top cotton wad."
* Remove item 5. The petroleum jelly lubricated the glass/neoprene
surface so that the neoprene stopper would not remain in place.
* Item 6 now reads, "a neoprene stopper is firmly inserted into the
test tube by twisting the stopper as it is being pushed into the open
end of the tube."
* In item 7 replaced "sticky tape" with "masking tape." The brown,
plastic carton tape did not adhere well to the glass of the test tube,
or for that matter to itself. Since the purpose of the tape is only
to secure stopper to the test tube (i.e., it is not expected to help
seal the test tube), I changed to masking tape. It did a much better
job.
* Remove step 8. The process of sealing the test tubes with wax is
moved to a separate paragraph below.
* Renumber this list, items 1 through 10.
In the paragraph which begins, "The control group is also constructed
similarly..." change "step (3) is not performed at all" to "steps (3),
(5) and (6) are not performed at all."
After this paragraph, add this paragraph -
"After assembling all thirty test tubes in this manner, they will be
sealed with several layers of parafin. The process is as follows:
1) fill a 2-quart saucepan 1/2 full with water;
2) put the saucepan onto an electric burner; don't apply heat
yet;
3) place a 250ml beaker into the water of the saucepan; to
keep the beaker from capsicing, secure the beaker to the
saucepan with tape;
4) place enough parafin into the beaker so that when it melts
the liquid will cover an inverted test tube approximately
0.5 to 1.0cm above the edge of the masking tape (in this
case, I used approximately 280 grams (4.5 ounces)); to
break the parafin, just score one side of a block with a
knife and snap the block along the score mark;
5) apply maximum heat until you see wisps of steam on the
surface of the water, then reduce the heat to a low setting
to keep the water at this stage - DO NOT allow the water to
boil, or you'll have a tough time getting your hand near
the beaker, and water will splash into the parafin;
6) once the parafin melts completely, take one test tube from
the rack, hold it upside-down at the bottom (closed end),
and dunk it into the beaker so that the stopper and tape
are completely submerged;
7) quickly remove the test tube from the parafin, shake off
any excess and place it back into the rack;
8) repeat (6) and (7) until all thirty test tubes have been
dunked in the parafin;
9) repeat beginning with (6) until each test tube has been
dunked in the parafin five times (i.e., you have to build
up the wax covering - kind of like making candles using the
dip method."
CARRYING OUT THE EXPERIMENT -
The first paragraph now reads:
"After the test tubes are prepared, and after their initial weighing,
they are placed into the wooden rack. The rack is set onto a
temporary shelf outside in front of a south-facing window. This is to
ensure that they get direct sunlight. Except for the time when the
test tubes are being weighed the rack and the test tubes will be on
this shelf."
In the detail of the weighing sessions, the times given have been
moved up 1/2-hour. Thus, 9:00pm is now 8:30pm, and 9:30pm is now
9:00pm.
The second task under the 8:30pm task list is changed to read, "remove
the wooden test tube rack from the window shelf and set it on the
table."
The fourth task under the 8:30pm task list is changed to, "set aside a
plastic or latex glove, to be worn when handling the test tubes." I
found out after building the test tube rack and sealing the test tubes
with parafin that grabbing the test tube so that it can be removed
from the rack would mean having to grasp the clamp over the parafin.
This would risk scraping off sections of the parafin, which would ruin
the integrity of the weight measurements. To keep from getting skin
oil on the test tubes, I decided the easist way to do this was to wear
a plastic glove on the hand that handled them (in my case, the left
hand).
There is one change in the paragraph under the 9:00pm task list that
begins, "This will be done in five passes..." The sentence "The test
tubes will be handled only using the test tube clamps..." is changed
to read, "The test tubes will be handled only with the gloved hand..."
The sixth task under the 9:00pm task list is changed to, "return the
test tubes to the wooden rack and set the rack outside on the window
shelf."
The last paragraph of this section has some changes as well. To the
sentence that begins "For this experiment, I am using a glass lens..."
I added the word "cylindrical" before the word "glass." The
measurements of this lens are 63mm by 29mm, not "5.5cm x 2.1cm." In
the next sentence that begins, "This item will be wrapped in a large
sheet of lens tissue..." I replaced the words "lens tissue" with
"bubble wrap." Likewise, in the next sentence, "tissue" is replaced
with "wrap."
<END>