DOI Page / Citation link:
https://doi.org/10.11588/diglit.33567#0219
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part. Four tackles were also rigged to pull the cradle along to the left as the monolith was lowered.
As a precaution against a possible yielding of the ropes at any time, a heavy movable strut was
devised and placed against the Needle, near the middle, the upper end being seized by an iron collar
round the shah, which formed the axis on which it could revolve, the lower end being free to move
away to the right when desired. To afford means of checking this movement so as to make it
support the weight, a roller was placed between two parts of the strut (see
jAW, Plate xxxviii); two ropes were wound several times round this roller, and the ends secured to
the columns of the scaffolding ; the roller revolving permitted the foot of the strut to recede as the
obelisk was lowered, but by placing a lever in a mortise cut for the purpose, this rotation could be
stopped, and the strut kept steady. As a prop of this kind could only act efficiently at certain
favorable angles, several were prepared of different lengths, so that at no period of the descent need
the obelisk be left without proper support.
All the preparations for the new work were completed by the yth of May, and the operations
were resumed on that day. The trumpet and the bell were used as before to regulate the capstans.
As the lowering tackles were slacked, the cradle and the heel of the monolith were pulled away to
the westward. It was Fontana's intention at first to keep the lowering tackles nearly vertical, but
as the work progressed that had to be given up; toward the end also the thrust of the obelisk
was such as not only to render the four tackles on the heel unnecessary, but to require one from
the opposite direction to check it. To prevent all shock in landing it, five tackles were also taken
from the point of the Needle to the arch of the sacristy of St. Peter's. The operation was entirely
successful, though frequent interruptions were necessary to rig the new tackles, and to remove cross-
beams of the scaffolding that were in the way of the descending shaft. By four o'clock the obelisk lay
safe and sound on the cradle, and, amid shouts and universal greetings, Fontana was carried home in
triumph escorted by drums and trumpets.
The monument had now to be dragged to its new site in St. Peter's Square, a distance of two
hundred and seventy-five yards. The level of the ground here was a little more than twenty-nine feet
lower than at the old site, but when the height of the pedestal, twenty-seven feet, was considered, it
was found that the descent would be only about two feet in the two hundred and seventy-five yards.
A roadway of earth was built on that grade, the sides being supported by a wood revetement propped
up by struts ; the revetement was further supported from within by transverse and diagonal braces. The
height of this viaduct increased from zero at the old site to twenty-seven feet at the new, the breadth
being seventy-three feet at the bottom and thirty-six and one half at the top. The obelisk was only
hauled away clear of the pedestal at first, so as to admit of taking down the scaffolding, and of
removing the underlying masonry, which was rebuilt in precisely the same shape at the new site. The
foundations required a great deal of labor and expense, as the nature of the ground was not favorable
for supporting a heavy weight. An excavation forty-three feet square had been made to a depth of
twenty-four feet, and as the soil then reached was not firm enough, oak and chestnut piles eighteen
feet long and nine inches in diameter, after being barked, were driven in a solid mass. Over this was
laid an immense bed of concrete, reaching nearly to the ground level, made of basalt and a mortar
composed of lime and puzzolana.
As Fontana dug down to unearth the old pedestal, he found the various courses laid as follows,
beginning with the top. First was a plinth ninety-six and one half inches high, one hundred and seven
and one half broad on the east side, one hundred and fourteen and one quarter on the west, and one
hundred and sixteen and one half on the north and south; the weight was computed to be fifty-five and
one half tons. Under this was found a block thirty-five inches high, one hundred and thirty-two inches
broad at the top, and one hundred and fourteen and one quarter at the bottom, weighing twenty-two
and one half tons. Then came another plinth one hundred and fourteen and one quarter inches high,
part. Four tackles were also rigged to pull the cradle along to the left as the monolith was lowered.
As a precaution against a possible yielding of the ropes at any time, a heavy movable strut was
devised and placed against the Needle, near the middle, the upper end being seized by an iron collar
round the shah, which formed the axis on which it could revolve, the lower end being free to move
away to the right when desired. To afford means of checking this movement so as to make it
support the weight, a roller was placed between two parts of the strut (see
jAW, Plate xxxviii); two ropes were wound several times round this roller, and the ends secured to
the columns of the scaffolding ; the roller revolving permitted the foot of the strut to recede as the
obelisk was lowered, but by placing a lever in a mortise cut for the purpose, this rotation could be
stopped, and the strut kept steady. As a prop of this kind could only act efficiently at certain
favorable angles, several were prepared of different lengths, so that at no period of the descent need
the obelisk be left without proper support.
All the preparations for the new work were completed by the yth of May, and the operations
were resumed on that day. The trumpet and the bell were used as before to regulate the capstans.
As the lowering tackles were slacked, the cradle and the heel of the monolith were pulled away to
the westward. It was Fontana's intention at first to keep the lowering tackles nearly vertical, but
as the work progressed that had to be given up; toward the end also the thrust of the obelisk
was such as not only to render the four tackles on the heel unnecessary, but to require one from
the opposite direction to check it. To prevent all shock in landing it, five tackles were also taken
from the point of the Needle to the arch of the sacristy of St. Peter's. The operation was entirely
successful, though frequent interruptions were necessary to rig the new tackles, and to remove cross-
beams of the scaffolding that were in the way of the descending shaft. By four o'clock the obelisk lay
safe and sound on the cradle, and, amid shouts and universal greetings, Fontana was carried home in
triumph escorted by drums and trumpets.
The monument had now to be dragged to its new site in St. Peter's Square, a distance of two
hundred and seventy-five yards. The level of the ground here was a little more than twenty-nine feet
lower than at the old site, but when the height of the pedestal, twenty-seven feet, was considered, it
was found that the descent would be only about two feet in the two hundred and seventy-five yards.
A roadway of earth was built on that grade, the sides being supported by a wood revetement propped
up by struts ; the revetement was further supported from within by transverse and diagonal braces. The
height of this viaduct increased from zero at the old site to twenty-seven feet at the new, the breadth
being seventy-three feet at the bottom and thirty-six and one half at the top. The obelisk was only
hauled away clear of the pedestal at first, so as to admit of taking down the scaffolding, and of
removing the underlying masonry, which was rebuilt in precisely the same shape at the new site. The
foundations required a great deal of labor and expense, as the nature of the ground was not favorable
for supporting a heavy weight. An excavation forty-three feet square had been made to a depth of
twenty-four feet, and as the soil then reached was not firm enough, oak and chestnut piles eighteen
feet long and nine inches in diameter, after being barked, were driven in a solid mass. Over this was
laid an immense bed of concrete, reaching nearly to the ground level, made of basalt and a mortar
composed of lime and puzzolana.
As Fontana dug down to unearth the old pedestal, he found the various courses laid as follows,
beginning with the top. First was a plinth ninety-six and one half inches high, one hundred and seven
and one half broad on the east side, one hundred and fourteen and one quarter on the west, and one
hundred and sixteen and one half on the north and south; the weight was computed to be fifty-five and
one half tons. Under this was found a block thirty-five inches high, one hundred and thirty-two inches
broad at the top, and one hundred and fourteen and one quarter at the bottom, weighing twenty-two
and one half tons. Then came another plinth one hundred and fourteen and one quarter inches high,