"Spirit Doors" or Split-Wedged
Sometimes when walking in the woods in Eastern Massachusetts, you come
up to a rock with a split in it and notice that someone jammed a rock
or two down into the split. At first I noticed this without giving it
much thought - probably having jammed a rock down in a split myself,
one time or another. If you had asked me about it, I would have said it
is not surprising to find these rocks in the woods, since there has
been plenty of time for people to walk by and casually jam a rock down
into a split.
But, if you look, you will see a number of examples where it would take
significant effort to lift up one part of the rock while putting in a
wedge. Try to imagine how someone could build the one shown next. You
can see it would be anything but casual. With an upper rock weighing a
thousand ponds or so, this is not the work of a passing boyscout.
Someone exerted themselves here.
I am not sure when I started paying closer attention to this
phenomenon; it could have been while walking in the woods with friends
and looking for examples of things that had been altered and showed
signs of being the "works of man". We go out hoping to catch a glimpse
of what the Indians might have done or might have left behind. I am
sure we discussed whether some of the split-wedged rocks might have
been done by Indians. There was also an article (online at Anthropology In the News;
more specifically this is from Sally's
Rockshelter and the Archeology of the Vision Quest by David Whitley, Cambridge
Archeology Journal (1999)) that talked about a practise among some
shamans of the Mojave desert where they placed fragments of quartz into
crack in a rock, believing the crack was a doorway to the underworld
and that they were making an offering to the spirits there. We
discussed that and other theories about why an Indian would wedge a
split rock and whether an Indian ever did that sort of thing around
No doubt plenty of split-wedged rocks could have been created by casual
passers by. Maybe wedging rocks was a popular fad at some point. Maybe
it was done for a practical reason. But even when split-wedged rocks
could have been made without much effort, I look at some and wonder:
what kind of impulse led a person to do that? Sometimes they are quite
Other times they seem like distinct structures with a specific purpose.
Split-wedged rocks do not appear everywhere in the woods. There are
places where the rocks have lots of splits and no wedges (for example
in Falmouth on the Cape) and other places were there are lots of splits
and lots of wedges. Sometimes they seem to be done compulsively in a
certain area, following a principle like "no split goes un-wedged". For
example, if you are driving north on Rt 3, as you pass under Rangeway
Rd in Billerica there are a half-dozen or so split-wedged rocks in the
woods on either side. Somehow, there, most of the split rocks got
wedged - as if it was important to someone.
I observe that split-wedged rocks are not very common in dry woods.
Rather they are usually adjacent to where water comes out of the
ground, at a spring. They are often found near the base of a hill but
are rarely near the top of a hill. They are usually found near rock
piles. To continue with the example of the crossroads of Rangeway Rd
and Rt. 3 in Billerica, here there was a stream, or a water source,
that drained eastward. The woods, in all four quadrants cut by the
roads, show multiple signs of the "works of man", including rock piles,
little walled embrasures, and large rock fragments - broken off of one
rock and placed on top of another. There are many small modifications
to the rocks here which, individually, would not seem remarkable; but
taken together suggest an unusual activity at this location.
One thing is certain: the wedging of rocks is widespread in the woods
north of the Concord River. I have looked and found very few of them
south of the Concord river. This could be a matter of not looking hard
enough, though I have tried to explore conservation lands, state, and
some private property, in all the towns surrounding Concord Mass.
Split-wedged rocks are common in Acton, Carlisle, and Billerica, and in
northern Concord, but they are rare in southern Concord, Bedford,
Lincoln, Lexington, Sudbury, Weston, etc. I have looked but only found
one on the Cape, and did not see any on a visit to western Mass.
Looking further afield: there are some split-wedged rocks at Madison
Springs in the White Mountains in New Hampshire, between Mount Adams
and Mount Madison. When it comes to a split-wedged rock above tree-line
in the mountains, we have something which is neither casual nor
practical. So what is it?
I have asked a few Indians about split-wedged rocks and some say they
have seen them (as far away as in Michigan) but don't know what they
mean. I asked Jim Mavor one of the authors of Manitou, a source book on Indian
prehistoric ceremonial stone work, and he has not noticed split-wedged
It is worth entertaining the possibility that these are not casual
items but, at least sometimes, were built with effort and for a reason
at specific locations. I cannot imagine a colonial farmer, or anyone
else leading a purely practical life, taking the time to go wandering
systematically though the woods wedging rocks. Nor would casual
creation of split-wedged rocks have resulted in them being concentrated
in certain locations and not in others - why are there more of them
north of the river than south of the river? Why, in some places, does
there seem to be something compulsive going on, something almost
ceremonial? And this leads to speculating about the Indians. The
Indians did live around here, they did work with stone, and they did
pursue ceremonial activities involving the natural landscape. Also they
might have been limited by natural territorial boundaries such as
rivers. The Indians are good candidates for who, besides casual walkers
or practical landworkers, could have created these "works of man".
If split-wedged rocks were made by Indians, what could have been the
reason for it? The article I mentioned provides a clue but one
speculates in different directions. Several people have come up with
this explanation: that the wedge represents an insemination of mother
earth, as represented by the split. The association with springs,
water, and fertility makes this plausible; and some examples certainly
provoke that thought.
I told a collegue at work about split-wedged rocks and he came back the
next day, excited because he had figured it out: "If a crack represents
a doorway to the underworld, and a spirit comes out of the crack, then
you need to prop the crack open, so it doesn't shut and trap the spirit
outside". This is my favorite theory and the reason we sometimes call
split-wedged rocks "Spirit Doors". Possibly, if the notion of a
doorway is appropriate, some splits could be filled with multiple rocks
to block the doorway instead of keeping it open.
In any case, split-wedged rocks are a real phenomenon, possibly with
multiple "causes". They are not all ancient, and a lot of time the
split is not natural and is, itself, the "works of man". Here is an
example where the split was made using a steel drill, and then a thin
wedge of rock was inserted. Perhaps it was not the same person who
split the rock and who wedged the split. The drill work on the rock
looks like standard colonial rock splitting. A large fragment has
already been split off and a nice piece of granite has been removed.
But then someone took the time to insert a thin wedge. In this case
maybe there was a practical function for the wedge and they just left
off work before it was completed.
But that doesn't explain most of the examples illustrated here. When a
rock has been deliberately split and a portion is missing, it is fair
to assume that getting a nice piece of rock was the motivation for
doing the work. But what are we to think when a rock has been
deliberately split but no fragments removed? That is the case for
several examples illustrated here (eg the third and fourth picture
above and the one below). Is it possible some rocks were split
deliberately, simply in order to insert a wedge and leave it at that?
Is it possible that colonial farmers split rocks because they were tired of the Indians performing
worship there. [as described several years ago in a Boston globe
article about Carlisle, but I cannot find the reference] and in some of
those cases the Indians came
back afterwards to wedge the rock so the two halves would be again
joined - thereby partially restoring a vandalized rock?
Like detectives who try to reconstruct the details of an event, it is
fun to look at a split-wedged rock and try to imagine a scenario. Is
the split natural? Was any rock removed? Could the wedge have been used
as part of a process for splitting the rock? Is the wedge a different
kind of rock? How much strength would have been required? Could it have
Next time you go walking in the woods, keep an eye out for split rocks.
When I see a split rock, I always go up to it and look inside - will it
have a wedge? Ah! Peekaboo! There it is.