Millikan Pumpkin Drop Experiment


For all you curious darbs, here are stories of the beginning of the Pumpkin Drop as a Dabney House tradition.

QUESTION: When was the first pumpkin drop ever?


Answer #1: Larry West

actually I'm surprised this story isn't more widely known; perhaps only
Because it didn't start out as a pumpkin drop.

i don't recall how it started, but in the fall of 1971 a couple of us were
Talking late at night in Alley 1 about the physics of pumpkins and we
Estimated that the strength of the "skin" of a small, fresh pumpkin, coated
with acrylic, would be sufficient to withstand a 95% vacuum for at least 5
minutes.  And a pumpkin of sufficient size would, once evacuated of air,
float (given that "skin" volume doesn't increase nearly as fast as as the
internal volume).

This was before 24-hour grocery stores, at least in Pasadena, so we had to
wait till the next day to go out and buy a variety of pumpkins (we got about
a dozen as I recall, as round as we could find).   We dipped them all in
acrylic and let them dry and then again a couple more times, drying at
different angles for more even coverage.

The next day was Saturday... or at least we felt comfortable about borrowing
someone's vacuum pump, so we tried out the idea, using a basketball needle
and chewing gum (to cover the needle hole).   We imploded about half of them
(the really large ones), and found that the smaller ones became peculiarly
light (and cool) but didn't float.  But two of the medium ones did float.
One got stuck under the rafters of alley 4.

The other, though, floated out of the courtyard.   We followed it along as
it rose, and watched it float along until it hit the side of Millikan
Library, abou t half-way up, and appeared to crack or somehow lose
containment, and fell to the concrete.   By sheer luck it missed a wandering
family.   We decided this was no time for finger-pointing or recriminations
and just wandered away.  Later we heard that someone else had fabricated a
story about a "pumpkin drop" just to rile the administration.  But of course
the funny thing is, next year it became a reality.

-- Larry West

Answer #2: Charles Nichols

Back when men were men and wild pumpkins strode the earth, I recall
co-instigating the first pumpkin drop. Other co-instigators probably
included Dave Levy, Fred Harris, Mark Parisi, Channon Price, and many others.

I think the idea came in two parts. The first was, "What happens when you
freeze a pumpkin?" The answer turned out to be "it cracks from thermal
stress". It took several tries to learn the advantages of pre-cooling
pumpkins in a refrigerator, transferring to a freezer for a week, and then
introducing them to the joys of dry ice and/or liquid nitrogen, both of
which were available via honor system cash boxes.

Once you have mastered the freezing process, you need to find something
worth doing with a frozen pumpkin. This was the second part. Since I was
already an accomplished lock troll on Halloween of 1972, and had a Millikan
Library master key in my collection, it seemed natural to go to the highest
spot on campus and drop it from the library roof. Especially given the
irresistable pun of the Millikan oil drop experiment (which measured the
charge of the electron, and which I had performed in high school.)

Thus was born the great Millikan Pumpkin Drop Experiment.

We gathered a crowd from Dabney House, situated them in a casually milling
crowd at street level, clued in the library sitter (then a Dabney House
sinecure (look it up)), and took a collection of pumpkins filled with dry
ice (the liquid nitrogen kept dribbling out of the cracks) up to the roof.
We waited for the stroke of midnight, then began releasing pumpkins over the
side. The result was spectacular. The pumpkins hit the concrete below with
an explosive report, an inexplicable flash of light, and a shower of deadly
shrapnel worthy of a fragmentation grenade. Fortunately, no one was injured.
The pieces made nice souvenirs, shaped like fragments of a shattered
spherical glass shell.

I participated in several more, before younger Darbs took over, so they all
ended up blurring together in my so-called memory. I particularly remember
that one year the ground had been saturated by heavy rains. One small
pumpkin missed the concrete and landed in a rose bed with a memorable
"schloonk" sound. It left in its wake a cylindrical hole, with a hint of
orange about four feet down. We left it for B&G to ponder.

The above may be semifictional. I did my best.

I now live in the Boston area, surrounded by MIT tools. I have learned that
MIT students were once, and most probably are still, performing the pumpkin
drop experiment on their campus as a Halloween tradition. I'm told it's
quite a popular event.

-- Charles Nichols

Answer #3: C.P. Price

how about a word from someone who was on the roof of millikan for the 
first two pumpkin drops (fall '72, possibly late october, sort of 
in conjunction with halloween, natch, and fall '73)? [you want the 
exact dates? check the Tech morgue...] the genesis of the idea, 
as for so many great ideas, does not have a simple exegesis. 
suffice it to say that 1) a sizable portion of the sophomores 
in fall '72 had done a little experiment called the millikan oil 
drop the previous spring, 2) as seen by the events of the previous 
spring (q.v.), things involving the roof of the (then) new library 
were terribly exciting, and 3) much craziness was in the air  
[gracious: sometimes it just has to be stated explicitly...]. 
(also, it gave us a huge challenge: prior to the opening of the 
library, the entire campus was accessible through just two master 
keys. the new library was keyed with the fiendishly clever medeco 
system, completely unpickable. so: how to gain access, short of the 
taking the route pioneered by jk? {the following year, the security 
guards were just as interested as we were...}) someone suggested 
that soaking the pumpkin in LN2 would make for an even more 
interesting event. someone else developed, in a )dare i say brilliant) 
leap of intuition, the theory that the collision with terra firma 
would cause the pumpkin to produce a brief but intense flash of 
light. now the deed had a genuine scientific purpose, an undeniable 
legitimacy in the place where pure research is now and ever held as 
the goal of greatest good: to see the flash of the pumpkin. (i regret 
now that we did not seek to assemble spectrographic equipment in order 
to fully record the process.) the subterfuge was run, the door was 
propped (sometimes the low tech solution _is_ the best...) and the 
research team assembled after dinner. shortly thereafter, the fated 
fruit (vegetable?!?) emerged from the depths of crellin, venting gouts 
of frigid N2. a select subset of the research team conveyed to the top, 
and after considerable urging by the rest of the observers, dispatched 
it to its glorious fate. none of the assembled, at either level, saw 
the flash. (well, there was one frosh who said he saw a flash, but as 
seen subsequently this person was always seeing the light...) we didn't 
see it the following year either, from frozen or fresh pumpkins (two 
frozen and one fresh). we did learn two salient facts: 1) the pieces 
from a frozen pumpkin travel a hell of a lot further than do the 
fragments from a fresh pumpkin, and 2) it is a hell of a lot easier to 
clean up after a frozen pumpkin (except for that little mound of really 
high density ice that appears right at ground zero...). oh, and the 
frozen pumpkins make a very solid `whump' when they hit, and the fresh 
pumpkin made a `splot' when it hit. 

i begged off the following year, when a pair of obnoxious frosh insisted 
that they be allowed to lob a couple of cans of 40 weight off the roof. 
the drop went with just pumpkins, but that brush with irresponsibility 
was just too much for me, and i retired from that field of scientific 
endeavor.

-- C.P. Price


Answer #4: Peter Groom


Hi, my name is Peter Groom and I am a Darb from the 1971-1975 era.  I
graduated in 1975.
 
I want to add this note to the Pumpkin Drop section of the history of
Dabney House.
 
I came to Dabney in September 1971 as a frosh.  On Halloween night of
1971, a group of Darbs stole the display pumpkins put out by food service
from all the student houses.  The pumpkins had not been carved.
 
A group of us took the pumpkins to Milliken, where a fellow Darb was
working that night, who got us admittance to the roof. 
 
We threw the pumpkins off from the corner facing Bridge.  A couple of
guys missed with their pumpkins, landing them in the planter in the
dirt.  I hit the walkway dead on with mine, so I got to throw the last
one, which was a giant one, maybe a 20-25 pounder. 
 
Two guys helped me, one on each side, as we maneuvered it into position. 
One, two, three!  I was the last to let go, and it rotated backwards
slowly as it fell, speeding faster and faster down a big cone, converging
abruptly onto the walkway.  A friend on the ground, Jorge Gustavson, said
that pieces of the big one hit the side of Bridge.
 
I don't know whether pumpkins had been dropped off Millikin previously
(the building was completed in 1966)  but I was there when we did it in
1971.   




Since 1972