Washington Monument
A History
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Chapter V:


The iron framework in the interior of the monument consisted of two parts: one carried the stairs and landings; the other the elevator machinery and car for hoisting the stones. The stair framework consisted of four wrought-iron Phoenix columns, seven and a quarter inches in diameter. They were located at the four corners of a square 15 feet, eight inches on an edge and concentric with the hollow well of the shaft of the monument.

The elevator shaft was formed by four Phoenix columns, six inches in diameter and placed at the four corners of a square nine and one-half feet on an edge, and concentric with the square formed by the four columns of the staircase frame. These columns were securely fastened and braced to the columns of the staircase. Guides and ratchets for the safety pawls of the elevator were fastened to the northwest and southeast columns. An iron framework carried the large pulleys for the hoisting ropes and other minor parts of the mechanism on the top of these columns.

The eight columns mentioned above were built to a height of 30 feet above the masonry shaft and were firmly tied and braced with vertical and horizontal ties and braces, making a rigid structure. To each of the four outer columns of this framework, a crane arm was attached so that it swung out over one-quarter of the top of the wall. Each of these arms had a mast 18 feet in height and a boom 19 feet, 6 inches in length, and was supplied with a traveling car and differential hoisting pulleys.

By means of this arrangement, 20 feet of masonry could be added to the height of the walls of the monument at one time. The process was then repeated and 20 feet was added to the height of the iron frame and the elevator and stone—setting machinery was moved to its top so that another 20 feet of the wall could be built. This method of first constructing 20 feet of the iron framework and then 20 feet of the wall was successfully continued to the top of the monument without incident. The load capacity of the elevator was six tons with a more than adequate safety factor, and it could easily complete 5-1/5 trips per hour to a height of 170 feet.

Construction of the stair landings went along at the same pace. At 20—foot levels, one above the other, 9—inch I—beams were passed through the two east and the two west columns. The ends of these beams were firmly secured in the north and south walls of the shaft. These I—beams formed the inner edges of the strong wrought-iron frames that constituted the landings of the monument. The outer edges were made by 9-inch channel bars the ends of which were firmly secured in the north and south walls. The landings were thus located along the east and west faces of the well and so spaced vertically that any landing on the east wall was 10 feet above the landing below it on the west wall. These landings were then connected by iron staircases along the north and south faces of the well, the inner carriage of the stairs being bolted into the Phoenix columns.

The Phoenix Iron Company of Trenton, New Jersey, was the principal contractor for supplying and erecting the iron framework of the interior stairway and elevator. Contracts were made with them for furnishing and installing the wrought and cast iron in 1881 and 1883. In 1882 J. B. & J. M. Cornell of New York City supplied the wrought and cast ironwork; and in 1884 additional material was supplied by H. H. Ramsay & Son of Baltimore, Md. In 1885, Snead & Co., of Louisville, Kentucky, were the principal suppliers of the iron work for the interior stairs and platforms as shown on Table IV.



Date Contractor Item Cost

July 6, 1880 Riordan & Driscoll
Washington, D. C.
Misc, Materials &
building 380 & c.m.
remaining feet of
stone cutting of sheds
$9 per running

Aug. 2, 1881 Phoenix Iron Co.
Trenton, N. J.
Wrought & Cast
Iron Work

May 11, 1882 J. B. & J. M. Cornell
New York City
Wrought & Cast
Iron Work

April 19, 1883 Phoenix Iron Co.
Trenton, N. J.
Wrought & Cast
Iron Work

1884 H. H. Ramsay & Son
Baltimore, Md.
Wrought & Cast
Iron Work
$ 1,045.00

Jan, 27, 1885 U. S. Electric Light Co.
Washington, D. C.
Electric light
$ 1,872.00

May 6, 1885 Snead & Co. Iron Works
Louisville, Ky.
Iron Work for
Interior Stairs

June 30, 1885 Dennis O'Leary
Washington, D. C.
Inserting memorial
blocks in walls
$ 1,825.00

Aug. 7, 1885 Ledig & Herrlein and SONS
Phila, Pa.
Cower & Gold-plated
lightning rods
$ 1,271.00

Oct. 22, 1885 William Bradley
Washington, D. C.
Stone Boiler
$ 6,994.58

1. ARJC for 1880-85, passim.

On January 13, 1880, the Phoenix Iron Company commenced work on the monument and by March 17 had completed the first phase to the starting point of the new work. Temporary treads and platform coverings of wood were thereafter installed to the top of the shaft. On April 1, 1880, Otis Brothers & Co., of New York City, began installing the elevator machinery and it was tested and accepted by the engineer in charge on July 12, 1880. Meantime, the apparatus for lifting and setting blocks of stone atop the shaft was completed and in working order by July 15.

With the completion of the foundation and before work could begin upon the masonry of the shaft, a reorganization of the working force was required along with a rearrangement of the machinery and plant. On June 1, 1880, stone cutting was begun and by October 15 the work force had been increased to 120 stonecutters, the largest number that could be accommodated by the buildings and tools. To the previous 76 feet of stonecutting sheds, 380 feet of new sheds were added and equipped with the necessary machinery. Additional railroad cars and turntables were added to the railroad spurs and 2,632 feet of additional track laid down within the area to facilitate the handling of the heavy stone blocks. With the permission of the District authorities, the marble contractor was authorized to construct this track to the grounds of the Washington Monument from the Baltimore & Potomac tracks on Maryland Avenue. This permitted delivery of marble from the contractor's quarry in Maryland direct to the stone sheds. Nine new blacksmiths' forges were constructed and five heavy Boston derricks were erected and supplied with hoisting gear. Foundations and houses for the boiler and engine of the elevator machinery were constructed.

Certain precision instruments and other materials were required to facilitate construction of the shaft. In 1881 new winding spool heads were installed on the hoisting engine; the elevator platform was strengthened; new turnbuckles were placed on the ends of the hoisting ropes; stays were placed upon the I-beams to the lower portion of the Phoenix columns in the well; and four bracket arms were constructed to be used as plumb spots in building the masonry. Another plummet 220 feet in length was permanently suspended in the southwest angle of the well; and eight leveling spots were adjusted upon the sub—foundation. Two new hoisting' ropes, each 1,060 feet long, were placed in position to facilitate work as the height of the obelisk rose. Colonel Casey was now ready to go ahead with his plans for completing the monument within four working seasons, 1881 to 1884. [1]


Before authorizing the commencement of work on the shaft, Colonel Casey ordered an investigation of the condition of the 26 feet of secondary stones that had been set by the Know-Nothings in 1858 atop the original 150 feet that had been completed by the Washington National Monument Society. It was found that the top portion of the shaft had disintegrated and the facing stones had been displaced and spalled. The three courses of stone were removed from the monument. Work was started on July 15, 1880, and completed by August 2. This alteration was to leave a permanent dividing line on the monument which is particularly noticeable in damp weather.

Setting of the new marble facing then went ahead and on August 7, 1880, the first stone in the new structure was set. By the end of the year 22 feet had been added to the height of the monument, and 32,118 cubic feet of masonry were used in its construction. As noted earlier, this was also to involve the construction of 20 feet of the interior iron framework and the shifting of all the hoisting machinery from the 180 to the 200 foot level. Table VI gives the figures for the annual setting of the marble and granite.

An added safety measure was introduced against lightning in 1880 when the four iron columns of the elevator shaft were grounded to the water in the well at the center of the foundation. An eight foot safety rope net was also stretched around the top of the monument as its height progressed to catch falling workmen. Fortunately, no workmen were killed during construction of the monument. Swinging scaffolds were also built and swung into place to enable the masonry to be pointed up as the work progressed.

During 1881, 74 feet was added to the height of the monument which then stood about 250 feet above its base. This work involved the cutting and setting of 1,184 blocks of marble, containing 42,261 cubic feet; and 1,348 blocks of granite backing for the marble, containing 44,349 cubic feet. Since August 7, 1880, when new construction work began on the shaft, a total of 100 feet was added to the obelisk.

According to Colonel Casey, the experiences of the 1880 and 1881 working seasons showed that the rapidity of construction work on the shaft was directly proportional to the supply of construction materials delivered by the contractors. Casey said this was especially true for the marble, of which Hugh Sisson was to remain the only supplier throughout the project. [2]

Each course of masonry in the shaft consisted of 32 blocks of marble and 24 blocks of granite. It took the stone cutters several working days to dress the blocks for setting, and the masons two days to build them into the shaft. A 20-foot section of the structure, including the erection of the 20-foot section of the iron framework, was built in 40 working days. Naturally, progress was limited by the quantity of marble on hand. Quarries had supplied an average of 103 blocks per month. This was equivalent to about 3.2 courses or 6.4 feet in height of shaft per month, or a total of about 77 feet of shaft per year. Casey estimated that at the above rate it would take three working seasons (1882, 1883, 1884) to complete the obelisk to its projected height, unless the marble quarries could develop greater capacity. Casey thought it was "probable" at the time. Since all the marble was contracted for with Hugh Sisson, who get his marble from the Beaver Dam quarry as noted, it is difficult to see how Casey anticipated increased deliveries. [3] His experience with the Lee Marble Co. of New York two years later in 1883 was to prove that contracting with one supplier for his special grade of Symington marble was still the best bet.

Since the completion of the foundation on May 29, 1880, a total weight of 22,353 long tons had been added to it. The subsidence of the four corners of the shaft from this additional weight was an average of .81 inches for the year.

The principal result of operations during 1882 was the addition of 90 feet to the height of the monument, which then stood at 340 feet above the base. This involved the cutting and setting of 1,440 blocks of marble containing 44,292 cubic feet, and 700 blocks of granite containing 33,468 cubic feet.

As the walls of the obelisk increased in height the proportion of granite backing to the marble facing diminished. Only marble was to be used at the 450—foot level and thereafter as the use of granite backing blocks was to end. Although the rate of delivery of marble blocks had been greater than that of previous seasons, it was not great enough to insure maximum building progress.

The hoisting machinery still enabled a course of stone to be set in a day and a half. During 1882 the number of blocks hoisted each trip was doubled, thus allowing several courses to be added to the top of the structure in that time.

Colonel Casey reported that if the delivery of marble continued at the same rate that it had during the 1882 construction season, he felt that the walls and pyramidion, or roof of the shaft, could be completed 100 percent by July 1, 1884, and "certainly by the close of the working season [November 30, 1884]." [4]

Despite initial difficulties in the delivery of sufficient marble for the season's work, 70 feet was added to the height of the monument during 1883, bringing it to the 410-foot level from its base.

During the winter months of 1883, delivery of marble had been slow and irregular so that work could not begin on further construction of the monument until May 1, when a sufficient supply of cut marble was ready. By June 26, 30 feet had been added to the structure. Work then ceased, however, as the supply of marble was exhausted. Hugh Sisson of Baltimore having completed his contract for the delivery of 39,000 cubic feet. [5]

Meanwhile, on March 12, 1883, proposals to supply sufficient marble to finish the obelisk had been invited by public advertisement. On April 18, 1883, a contract had been entered into with the Lee Marble Company of New York, the lowest bidders at $1.29 per cubic foot, this being six cents less than the previous year's price.

Difficulties developed with the Lee Marble Company, however, and when it became obvious after three months of non—deliveries that the contract would not be fulfilled, it was cancelled on July 2, 1883. A new contract was entered into with Hugh Sisson on July 20, 1883, for the desired 42,000 cubic feet of marble, the cost then being $1.50 per cubic foot.

By October 1 a sufficient amount of marble had been processed to permit building to be resumed. By November 24, 40 feet of new masonry had been added to the shaft, making a total of 70 feet for the year and bringing the monument to a height of 410 feet above its base. Colonel Casey reported that greater progress would have been made had three months of the season not been lost by delays caused by negotiations with the Lee Marble Company.

Since the date of the new contract with Sisson, marble blocks were delivered at the rate of 200 blocks per month. Casey estimated that if this rate of delivery were continued during the winter and spring months of 1884, all marble for the completion of the shaft would be on hand by April 1884, thus making it possible to finish the walls and roof, or pyramidion by the close of the 1884 working season.

During the 1883 season, 1,120 blocks of marble containing 27,718 cubic feet and 490 blocks of granite containing 13,438 cubic feet were built into the structure. Since the completion of the foundation, 31,543 long tons had been added to the weight of the then-existing structure. The settlement of the shaft during 1883 reached an average of 1.65 inches for the entire structure. The total pressure on the foundation bed reached 78,060 long tons or nearly 97 percent of the total weight that was to be placed upon it. [6]

Construction continued on completing the shaft to its 500—foot height during 1884. On June 23, the last block of marble was delivered by Sisson and it was set in place on August 9, 1884, thus completing the shaft according to Colonel Casey's estimate in four working seasons.

During the 1884 season, 1,288 blocks of marble, containing 25,909 cubic feet, and 294 blocks of granite, containing 5,500 cubic feet, were built into the shaft. Owing to the thinness of its walls in the upper portions, additional care was taken in its construction between the 440 and 452-foot-levels, when galvanized iron clamps were freely used. From the 452 to 500—foot levels the walls were constructed entirely of marble, of "through blocks", and from the 470-foot level where the ribs of the pyramidion began, the several courses were secured to each other by mortises and tenons cut in the builds and beds of the stone. [7]


One of the outstanding engineering feats of the Washington Monument is the pyramidion which sits astride the top of the shaft from the 470-foot to the 500-foot levels. For historical purposes, the intricacies will be detailed here. Even though hit directly by lightning in 1884, investigation revealed that only a small chip of marble had been dislodged, the damage being easily repaired.

The pyramidion is 55 feet in height and weighs 300 tons or 627,000 pounds. It was built entirely of fine-grained marble supplied by Hugh Sisson of Baltimore, Md., the same contractor who supplied all the marble used in the construction of the monument from the 150-foot level up. The State of Maryland is as proud of its contribution to this outstanding monument of the world as it is of the Washington Monument at Mt. Vernon Square in Baltimore. The marble for the pyramidion was quarried at the Beaver Dan Quarry in Baltimore County, Md., and was delivered to Washington by the Baltimore and Ohio Railroad, Maryland's own.

The marble was strong and durable and weighed 178-1/2 pounds per cubic foot. It was the same marble that Robert Mills, the first architect and designer of the original plan for the Washington Monument, had tested at the Navy Yard under the aegis of the Secretary of the Interior in 1848 with such success. It was the same marble that was used in the facing of the balance of the monument, including the original 150-foot level completed by the Washington Monument Society. Bernard R. Green, the noted civil engineer whom Casey had selected to supervise various engineering details of the project, had designed the pyramidion and was completely responsible for its successful construction.

The covering slabs of the pyramidion are of marble but seven inches in thickness. Each of the slabs rests upon projections on the marble ribs. There are 12 ribs, three upon each side of the well, that spring from the interior face of the wall at the 470—foot level. The ribs are then carried upward until those nearest the angles of the shaft meet in the hips of the pyramidion, while those in the center of each face are connected still higher in the apex by voussoir stones or keystones, forming two arches intersecting each other at right angles. The thrust of a corner rib is transmitted to its opposite by the use of horizontal stones between their upper extremities.

Work began in June 1884 on the pyramidion by assembling materials and the machinery needed in its construction. On October 29, 1884, the last piece of marble for this part of the structure was delivered by the contractor Sisson, and on November 21 it was dressed by the stone—cutters. It took 30 days to set the marble of the pyramidion, the balance of the time since June 1884 being taken up in building and assembling the special machinery, platforms, and derricks required, and in dressing the marble. At the end of the 1884 working season. December 1, it was only necessary to fit the marble slabs then used as shutters to the eight openings for windows in the pyramidion for its completion. Colonel Casey reported in his Annual Report that this would take a few weeks. The pyramidion consisted of 262 separate pieces of marble, containing 3,764 cubic feet of dressed stock. In December 1884 the mammoth structure was lifted into place without incident and in one piece. [8]


In November 1884, Colonel Casey had about 118 workmen employed on completing the Washington Monument compared to the 57 employed as work demanded during the first construction phase, 1884—56. By this time wages had spiraled and had risen 100 and 250 percent above those of 1848, largely due to post-Civil War inflation. The type of workman, number and wages paid follow for the historical record. [9] The number of workmen naturally varied with the progress of the work and the amount of materials on hand.

Marble cutters 583.50
Marble cutters 103.75
Master stone cutter 15.00
Stone Cutter Foreman 14.50
Blacksmiths 53.00/3.50
Blacksmith, helper 12.00
Stone setters 14.25
Carpenters 42.75/4.25
Machinist 13.50
Rigger 13.25
Rigger, asst 12.50
Fireman 12.25
Laborers 82.00First class
Laborers 201.60/1.75Second class
Watchman, special 12.00
Water & tool boys 3.75/1.00
Engineers 22.75/3.25


To complete the obelisk, the aluminum capstone weighing 100 ounces, the largest single piece of aluminum cast to that time, was placed atop the pyramidion on Saturday, December 6, 1884. Colonel Casey was elated at meeting his deadline for completion of the Washington Monument.

Prior to delivery of the capstone in Washington, it was placed on exhibit at Tiffany's in New York City where it was placed on the floor and persons could have the dubious prestige of "jumping over the top of the Washington Monument." Engraved on the four sides of the capstone was the official record of the construction of the monument.

The west face read: "Corner Stone laid on bed of foundation, July 4, 1848. First stone at height of 152 feet laid August 7, 1880. Capstone set December 6, 1884"; and the east face read "LAUS DEO." The north and south faces contained names of the commission and the key men in the work of completion. Although weatherbeaten, the inscription is still visible.

The laying of the capstone was appropriately celebrated. At the top of the monument, a special scaffolding had been constructed where the principals involved with the construction of the monument could stand. As thousands of eyes were trained upward toward the pinnacle, a 60-mile—per—hour wind was blowing, and the footing was dangerous. According to S. H. Nealy's sketch of the ceremony, P. H. McLaughlin, project superintendent, placed the tip on the pyramidion as the rigger, James Hogan, released an American flag to signify the completion to the cheers of the crowd below and the booming of cannon brought from Fort Myer, Va., especially for the occasion. Also on the top platform were Bernard R. Green, civil engineer, Capt. G. W. Davis, assistant project engineer, Colonel Thomas Lincoln Casey, Chief project engineer, and Lewis O'Brien, foreman. [10]



Calendar Year 18802 18813 18824 18835 18846 18857 18868 18879

Appropriations 150,000.00150,000.00 150,000.00250,000.00
75,000.00 57,000.0050,000.00
Expenditures 267,542.52171,199.51 177,489.60130,042.31 141,085.3758,462.03 51,157.10112,356.48

Balance on Hand $82,457.4861,257.97 33,417.37153,375.06 12,289.6928,827.66 62,415.458a5,109.399a

1. Annual Report of Joint Commission for the Year 1880, Senate Misc. Doc. No. 9, 46th Congr., 3d Sess., p. 5, cited hereafter as ARJC. Includes annual report of engineer in charge, Col. Thos. L. Casey, C.E.

2. Ibid.

2a. Act of Aug. 2, 1876.

3. ARJC for 1881, Senate Misc. Doc. No. 19, 47th Congr., 1st Sess., p. 3.

4. ARJC for 1882, Senate Misc. Doc. No. 13, 47th Congr., 2d Sess., p. 3.

5. ARJC for 1883, Senate Misc. Doc. No. 22, 48th Congr., 1st Sess., p. 3.

6. ARJC for 1884, H. Reps., Misc. Doc. No. 8, 48th Congr., 2d Sess., p. 3.

7. ARJC for 1885, Sen. Ex. Doc. No. 6, 49th Congr., 1st Sess., p. 5.

8. ARJC for 1886, H. Reps. Misc. Doc. No. 57, 49th Cong., 2d sess., p. 3.

8a. No reason given for apparent discrepancy of totals.

9. ARJC for ARJC for 1887 Senate Misc. Doc. No. 22, 50th Congr., 1st Sess., p. 3.

9a. Same as for 8a.


Contracts for Marble & Granite1

White Marble Blocks Rough Granite Blocks

DateContractor Quantity
(cu. ft.)
Cost DateContractor ItemPrice
7-9-1880Hugh Sisson
Baltimore, Md.
40,000$1.00July 12, 1880 Davis Tillson
Rockland Me.
40,000 cu. ft..52 per. cu. ft.

5-17-1881Hugh Sisson
Baltimore, Md.
36,000$1.35May 18, 1881 Cape Ann Granite Co.
Boston, Mass.
26,000 cu. ft..49 3/4 cu. ft.

5-19-1882Hugh Sisson
Baltimore, Md.
39,000$1.35May 22, 1882 Bodwell Granite Co.
Rockland Me.
23,000 cu. ft..53 per. cu. ft.

4-18-1883Lee Marble Co.2
New York City
42,000$1.29Apr. 3, 1883 Wm. S. White
Rockland Me.
10,000 cu. ft..51 per. cu. ft.

7-20-1883Hugh Sisson
Baltimore, Md.


1. ARJC for 1880—85, passim

2. Contract canceled July 2, 1883, for non-delivery

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Last Updated: 18-Nov-2003