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How String Was Used In Laying Out Hezekiah’s Tunnel

By Robert Kerson 12/26/2012

rkerson@snet.net

Why and how was Hezekiah’s Tunnel dug with such a long and sinuous path? I can

demonstrate that the design was, in fact, not a random act of tunneling but was very

deliberately laid out according to a precise mathematical design. Then after a very long time

tunneling, the diggers succeeded in laying out the tunnel as planned. This paper will detail

possibly the whys and the how1.

Hezekiah’s Tunnel was worked out with some similarity in designing the Holy Temple built

to the north (see my scribd article:” How Jewish Temple Laid Out Using Measuring Cords”).

There was an association of the water flowing through the tunnel from the spring of Gahon to

the pool of Shiloh and the temple since water collected from the pool was brought up and

poured on a corner of the altar during the Feast of Booths. Isaiah makes allusion to water

drawing and the winding tunnel in chapter and verse 12:2-6 where the god of Israel equated

with the waters of salvation runs in the midst of Zion. (Zion was originally the city on the

eastern ridge under which this tunnel was located.)

The similarities are that the nearby temple and this tunnel utilize the same most important

ratio number in their construction, and also by simply using key number measurements from

natural features such as caves at the temple and tunnel sites. For example 135 Cubits was a

very important temple measurement as both the Azarah and Court of the Women had this

dimension, and the tunnel also utilizes this same number. (Very important point: the tunnel

used a common cubit2 (1 cubit= 44.3738 cm), while the temple was of a longer Royal Cubit

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(1 Cubit =52.5 cm) measure. Hence 135 cubits in the tunnel did not actually match the length

of 135 Cubits in the temple. ). The reason the tunnel was laid out in its serpentine shape was

to create a tunnel exactly 1200 cubits long, worked by two teams. The ancient inscription

tells us they actually measured the tunnel’s length, yielding a known cubit size of 44.3738

cm. (The total distance from spring to one or two pools was somewhat longer as it entailed

older sections of tunneling and pools farther to the south.)

A third possible reason can be because of a measurement I call Cherubim measure and is

discussed in my book Sacred Stones Sacred Stories vol. 1.

A fourth reason would be to allow the slope of the tunnel to be very gradual since the

longer the tunnel, the less the floor gradient would need to be.

After the whys comes the how. First I will state unequivocally that they knew exactly what

they were doing as they measured and laid out the tunnel exactly as planned. They absolutely

did not have three false tunnels, nor did they franticly zigzag near the meet point.

1. They located a few important landmarks and noted the actual straight line distance

between these locations. Finding they were all capable of being measured in

important short cubit lengths, they worked out a pattern on flat ground using

measuring cords which were essentially pieces of string cut to known lengths.

2. They transferred the design from landmark to landmark onto the surface of the hill

1 Figures are relevant tracing of tunnel diagram taken from Jerusalem- An archaeological Biography,

Hershel Shanks, Random House,1995, p.91 ISBN 0-679-44526-9 2 See The Historical Books 1

st and 2

nd Chronicles ,Marie S. Burns; Author House Publishers; 2005,

ISBN 1-4208-3673-0 (sc) 3 See The Quest, Leen Ritmeyer, carta , Jerusalem, 2006; p. 171, ISBN 965-220-628-8

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using much longer lengths of string and then anchored the string with rocks or sand

so as not to move. They started digging while people hammered the ground next to

the covered string (see Ayreh Shimron4).

3. Another set of strings, actual measuring cords were laid out from either ends inside

the tunnel as the two excavations moved forward until they met at the designated

meeting point.

Now that we have the basic ideas, we can go into the details.

(see Fig.1)- The genesis of the pattern was found in that the linear distance from a point to

the west of Warren’s Shaft which became the start of the tunnel labeled (4), to a point very

close to or even exactly on a natural sinkhole (10) was almost the linear distance of 600

cubits. (In fact extending the line a short distance eastward to the point labeled (d) would

make the line exactly 600 cubits. This extension was later blocked up.)

[Measuring distances of natural features also was used on the Temple Mount, and also I can

show, (but beyond the scope of this paper) that the mind who conceived this design also

worked on the Temple Mount located nearby. I can show that a similar hand worked on the

inner temple sacred square and inner temple courts which might date from the same time as

Hezekiah’s Tunnel.]

This line first laid upon the surface of the ground but later transferred underground in the

tunnel I call Line 1.

On the surface of the ground a measuring line was then laid from the purposed tunnel’s

southern exit point (g) to the previous sinkhole (10) site. This was Line 2. The distance of

Line 2 was then laid out along Line 1 from point (4). The end of this second line was at a

point marked on the ground and shown as point (7). This was the most important point of the

pattern and was marked underground in the tunnel by a special shaped niche—a so called

“false tunnel”.

A similar laid line on the surface I call Line 3- runs from point labeled (11) (Here at a later

date an inscription describing the tunnel’s length was written upon the wall), the start of

tunneling by the southern team at the spot the tunnel veered off from the line of a natural

crack on the ceiling of a cave to the point on Line 1 labeled (7).

The ratio of Line 3 / segment of Line 1 from points (4) to (7) is 1.612 which is very close to

the Golden Mean [1.618033989]. This number is also very close to the ratio of 8/5 or 1.6.

Then the following is true: 8 parts (Line 3) /5 parts (segment of Line 1 from points (4) to

(7) is 1.6. Reading my paper on the construction of the Holy temple built to the north, you

will discover the entire temple could have been laid out utilizing a triangle of 8:8:5 which

also has a ratio of 1.6. So the two most important lines for the construction of the tunnel,

have the same ratio for building the temple. Also, any measurements taken off of naturel

caves were similar to measurements taken off of natural features such as caves on the temple

site (detailed in my paper). This might imply the tunnel and the 500 Cubit square of the

temple were surveyed about the age of King Hezekiah’s rule.

From reading my paper on the temple, you will discover the same division of a line into 8

parts being the sum of 5 parts and 3 parts can be seen today in the northern edge of the

4 Journal of Archeological Science, Tunnel Engineering in the Iron Age:

Geomorphology of the Siloam Tunnel, Jerusalem, Amos Romkin, Ayreh Shimron, Vol.

33, Issue 2, Feb. 2006, PP. 227-237.

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existing Moslem Inner platform and in Ritmeyer’s 500 Cubit Square.

A fourth line running very close to Line 3, having one end on the same point (7) but the

other end was on the tunnel’s current exit point (g) instead of point (11), I will label this Line

4. Measuring along this line from point (g) 187 cubits marks the spot I label point (a). 187

cubits was an important temple length being the length of the inner courtyard measuring from

east to west.

The tunnel passes under the older Silowam Channel at two locations: at points (10) and (h).

A fifth line, called Line 5, starting from point (h) passed through Line 1 at a point labeled (b).

The length from point (10) to point (b) measured on Line 1 was 187 cubits, the east to west

distance of the inner courtyard of the holy temple. Also, the orientation of Line 1 mimics the

orientation of the eastern edge of the current Moslem Platform (See temple article). If this

edge was once within the Court of the Women, there would have been a connection between

the waters flowing through the tunnel and this court since on the nights of the rites of Water

Drawing during the Feast of Booths, four fires burning on top of tall poles were lit in the

Court of the Women.

Then the east-west dimension (187 cubits) of the inner courtyard would be present in these

lines (but using a different smaller cubit then the larger Cubit of the temple site.)

As stated previously the entire tunnel was worked by two teams working from either end

toward the middle for a total length of 1200 cubits. I believe the meeting point was to be dug

by the southern team 675 cubits, and by the northern team 525 cubits. Each of three niches

(the so called false tunnels but more correctly survey or measuring niches because they were

used in surveying key locations or measuring the length of the tunnel) were cut on the only

bends in the walls of the tunnel under the only two major lines creating the tunnel: Line 1 and

Line 3.

They measured along Line (1) the distance from points (4) to (b). Next they extended Line 5

from point (b), to locate a terminus of this line at a point (f), by taking half the distance from

points (h) to (f), a point labeled (j), and adding it Line 6, the distance from points (f) to (4).

[mathematically- the distance from (j) to (f) + (f) to (4) = distance from (4) to (b) where (j) to

(f) is half the distance from (h) to (f)].

From point (9) to point (f) a seventh line labeled Line 7 could then be stretched. Point (e)

was along this line. This point was close to point (j) on Line 5. Also from point (9) to point

(4) an eighth line labeled Line 8 could be stretched. Point (m) was along this line.

(see Fig. 2 tunnel is shown as a curving red with black dotted line)- Then a string or cord

675 cubits long could be curved on the surface of the ground connecting points (g), (11), (a),

(10), (h), (b). The remainder of the cord had to touch Line 3 at point (9) and run along Line 1

between points (8) and (7) before running out a short distance away at a point I will label

point (6). Stone or sand weights could then cover the string to immobilize it. The southern

tunneling team while using similar measuring cords and an instrument called a Groma

capable of laying out 90 and 45 angles could then cut out a tunnel below ground by

following the sound of the hammering above. In similar fashion, a string or cord 525 cubits

long could be curved on the surface of the ground connecting points (4), (f), (m), (e) where a

major bend would be located close to point (j) and ending a short distance away at point (6).

The northern tunneling team could then cut out the northern segment of the tunnel. Fig. 2

shows the resulting tunnel.

The tunnel has sweeping curves at either end, but zigzags near the meeting point, which

would be expected if the cords were laid out from (g) and (4) and the fixed lengths of each

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teams cords were tweaked to reach a single meeting point.

The number 500 which was the size of 500 Cubit square on which them temple was built

can be found in both the northern and southern tunnel lengths. The southern string length was

500 cubits+ 100 cubits+ 3/4 of 100 cubits (i.e. 75 cubits), and the northern segment is 500

cubits + 1/4 of 100 cubits (i.e. 25cubits). If we add the two fractions we get another100c. If

the 1200 cubit cord were to be divided into two 675 cubits and 525 cubits sections, these

sections would be 75 cubits from the exact center of the 1200 cubit cord (1200/2= 600).

If we subtract 3 cubits, the southern team would have to dig 675-3 cubits or 672 cubits to

reach a new meeting point. If we add 3 cubits the northern team would have to dig 525 +3

cubits or 528 cubits to reach the same new meeting point. If we take the ratio of these two

numbers, and square the results we get a close approximation of the golden ratio

[(672/528)(672/528) = 1.6180]. The tunnel inscription does mention the number 3 cubits. The

inscription may be describing the meeting point where the two teams met or instead they may

be describing the meeting point where they broke the wall allowing water to flow into the

tunnel at the northern end5.

Point (8) defined the straight line segment along Line 1 marked by what was to become two

bends in the tunnel from points (8) to (7). To have the meeting point at 675 cubits and 525

cubits and to have all other points on the cord be at the locations shown in Fig.1, the segment

along Line 1 cannot have any other dimensions other than from points (8) to (7). Also this

segment of the tunnel may have been a temple dimension as 11 cubits. So too the length from

points (8) to (9) may have been an altar size such as 28 or 32 cubits.

Another relationship is that the distance from (a) to (9) equals the distance from (10) to (7)

where both points (9) and (7) are niches (two so called false tunnels).

5 “The date of the Siloam Reconsidered”, Journal of the Institute of Archaeology of Tel Aviv University,

volume 38,nuber 2,November 2011, pp. 147-157

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Figure 1 top. Lines and landmarks shown. see text for discussions.

Figure 2 below. tunnel shown red and black dots. see text for discussions.

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As stated previously I have defined three important landmarks in the design of the tunnel:

points (9), (8), (7) cut by the southern team, which were on made on bends close to the

meeting point labeled (6). Point (9) was on the bend of Line 3. Point (8) was on the bend of

Line 1, and Point (7) was the only point common to both Lines 3 and 1. Each of these

landmarks where marked by carving out niches under these three points. Thus if you were to

stand in a niche, you would be standing under the string or cord snaking on the ground

overhead at key locations of the two main lines creating the design. The smooth finishing on

these niches were necessary not because of appearances (they do represent sacred geometric

locations), and certainly not because of mistakes in tunneling. They cannot be mistakes since

these three locations are not randomly placed.

They might also been created in the fine tuning of distances within the tunnel for example

the depth of the niche might add some additional measure to a longer measuring cord adding

possibly a handbreadth to make the niche the depth of a Royal Cubit etc. If so the niches

would have to be finely squared as two actually were. Niche at point (8) was not cut square

as may be expected since it appears to be cut in a unique fashion having only one side cut

square. This niche was unique as being common to both Lines 3 and 1.

(see Fig. 3)- No niche bends inward on itself as diagramed in the right hand illustration.

They bend outward or straight ahead at the bend which would be expected if the measuring

cord was laid without bending backwards. The curve diagramed on the left shows how the

cord would look if laid on the floor without the kink. All three niches are as shown in the left

hand illustration. The length of the measuring cord in cubits would be distance X (black line)

and the longer length of some Royal Cubit or some number of handbreadths would lengthen

the cord by a distance Y (black and red dotted line).

The ceiling rises slowly beginning at point (10) and very noticeably at the southern end.

The southern end was a natural cave which would account for the high ceiling, but

Since they knew the completed length of the tunnel to be 1200 cubits and the difference

in height from tunnel end to end (they had an earlier channel of the same heights) they

could determine when starting at each end the correct slope of the floor which cannot be

done if they did not know the tunnel’s length beforehand. The grade is 1 in 7 falling about

1.8 meters from Gahon Spring at the northern end to the pool at the southern end. They

must have used two oil levels with lines drawn at the correct slope.

(see Fig. 4)- The walls of the tunnel have a lip below the ceiling then a scalloping below

on the left wall while the right wall is flat (illustration A). ). Other sections of the tunnel

have the scalloping on the right wall but not the left (illustration B). Some sections have

scalloping on both walls (illustration C). At the southern end either little or no scalloping

or else the scalloping is on the lower portion of the wall (illustration D). The tunnel men

may have created the straight edge side closest to where they laid the measuring cord

(shown as a dot) otherwise the cord was placed in the center of the passage.

The teams could not reach the meeting point in three dimensional space without having the

tunnel’s course first laid out above ground. They could not randomly tunnel to frantically

reach this location in the hillside. Also they would know in advance the length of the tunnel

and then might possibly be able to know in advance if at this distance excavators could work

for such a distance without fresh air. All the mathematical and geometrical evidence

presented that the tunneling was deliberate is hard to refute.

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Figure 3 on top see text for discussions

Figure 4 below see text for discussions