copyright  Thomas G. Yanul
To begin to grasp the enormity of the task at hand you must start by taking a quick look at the timeline available.  Although discussions about a world's fair had been going on in Chicago since the late 1880's, final approval to start getting things done was not really given until November of 1890.  Shortly thereafter Daniel Burnham, the consulting architect from the Chicago firm of Burnham & Root, was named Chief of Construction. The group of architects chosen to actually design the buildings did not have their first meeting in Chicago until January 10, 1891, at which time they toured the chosen sites of Jackson and Grant Parks (the latter for construction of what would become the Art Institute of Chicago). Attached to the Construction department were Burnham's partner John Root as general architect in charge, Abram Gottlieb as engineer (later replaced by Shankland), and Olmsted & Co. for landscape. Root could not attend due to illness and died Jan.15th. The architects met again on February 22nd bringing their sketch plans for the individual buildings. The  start of construction - dredging and filling in the swampy area known as Jackson Park actually began February 11, 1891.
The first mention I have found for C.D. Arnold is March, 1891, for a construction photograph of a utility tunnel. [From - Expo papers held by the Chicago Public Library, Special Collections]. This confirmed date puts Arnold in a very early position; its quite possible he was there earlier, at the very first turn of dirt on Feb.11th but there is no actual confirmation yet.
To reiterate, exactly why Arnold is there so early we don't know.  Whether his contact was through one of the three large New York architectural firms involved (McKim,Mead and White; Richard M. Hunt; George B. Post) -or the Boston firm (Peabody&Stearns)  or for that matter possibly even Olmsted & Co.- who had done extensive work in Buffalo in the late 1870's where Arnold lived at the time, or even Charles B. Atwood, who worked in New York for the time Arnold operated there - its still a mystery. Obviously from what we know about Arnold becoming an architectural photographer, its likely that he had contacts with some or all of those firms. Its a moot point at this stage anyway. He's there early on and he's working as a photographer for Burnham's construction department.
The first actual building on the fair grounds was a temporary "shack" as it was known, for the Construction Department. It was staked out Feb.27,1891 and completed April 25th. That building was moved in May of 1892 to make room for the permanent construction office. Arnold operated out of both of these structures until his own building was completed at the end of October 1892.  [See photos Arnold bldg. right col.]


Although we know that Arnold was present in March of 1891 as a construction photographer, little is known about other employees either working for or with Arnold. As far as I can tell, only one other person is working  with Arnold, an "assistant" by the name of "Otto G. Scharff"  [correct name most likely Scharf] In a March 1892 report to Congress by the President of the W.C.E. all employees of the Corporation were published and included their position, salary, and state they were from. Arnold was simply listed as "photographer", pay of $125.(per month), from New York. Scharf is listed as  "assistant photographer", $75., also from New York. The Auditor's monthly reports were not begun until December of 1891 and they indicate that from at least from Dec.91 through October of '92 Arnold had one assistant, Scharf.

The first increases in numbers began in November of 92 at 4 people; December at 6.
For 1893: Jan-8; Feb-13; Mar-21; Apr-17; May-45; June-72;
July-95; Aug.-108; Sep.-86; Oct-77; Nov.45; Dec.25.
 For 1894: Jan-17; Feb.-10 and May-5.
Who these other people were are not known. Its certainly likely that most were clerks and people to process negatives and make prints [most of the prints were made with printing-out-papers which required sunlight to develop. This was most likeley done in the rooftop skylight areas seen in the rear of the roof area. It was a very labor intensive operation and of course could not be done on dark, overcast, or rainy days]
There certainly must have been more "operators" as cameramen were then called, but who exactly they all were is unknown.  Only two people other than Arnold and his assistant Scharf are known to have made photos, especially before the official opening of the Exposition. These were Harlow D. Higinbotham who would later become his businesss partner in the photo concession, and John J. Gibson.
Higinbotham was an accomplished amateur photographer some years before the fair. Family letters (1888-89) indicate a photography darkroom had been designed for him by architect F.M. Whitehouse in the family's new home being built on south Michigan av.
John J. Gibson, who became the Official Portrait Photographer, spent many months at the fair in 1892 working on getting his concession, and almost daily letters to his wife (running the day to day operations of his studio in Ann Arbor, Michigan) state he is "helping Arnold with some photography".
 [letters coll. of author]
Otto Scharf, whose name I believe is correct with only one "f" because an  autographed copy of the Official Photographery Dept. book [coll. author] given to Gibson by Scharf - is signed by Scharf with only one "f". the book is also signed by Otto's brother "C. Leo" which leads me to believe that he also worked for Arnold. City directories and census records for 1895 list Otto Scharf
- Jackson Pk., 62nd St." apparently still within the grounds of the fair. The next year both Scharfs are doing business as Scharf Brothers on south Dearborn St., Chicago, and subsequently in 1898-99 are in business in the old "temporary" exposition-period buildings on east 57th st., Hyde Park area of Chicago. (variously reported addresses of 212 57th; 214 57th; 265 57th.  
The listing for C. Leo disappears in 1909 and no further info was found for him.
A sister, Anna, works for Otto as "saleslady-picture store".  None of this family can be found in the 1920 census or directories in Chicago or New York City. In 1910 census records indicate Otto was born in Germany,
age 40. Sister Anna, who lives with Otto,is born in New York, age 34.
The 1880 census has a family of Scharfs that I believe Otto is from. Parents were Louis & Bertha. 5 boys-Rudolph, Marx, Leopold (poss C.Leo),Otto, Louis.
And 3 daughters-Lizzie, Anna & Bertha. Otto listed as photographer, and the family lives in Manhatten. Quite possible this contact for Arnold came from his 1880's-90's work in New York City
I am indebted to Harlow Higinbotham, grandson of Arnold's partner in the Col. Expo. and great-grandson to the fair's president.
Many of the photos of the Higinbotham family were shared with the author along with letters, and other importaint information.
 Construction Photography, pg.2
To Contact:

Two views of Arnold/Higinbotham
Official Photographer's building.
Top -  from A History of The World's Columbian Exposition
by Rossiter Johnson, V.-II, 1897
Bottom - From an actual photograph (dated Mar.13. 93) showing the position of the building.  62nd St. is leading off to the left where there was an entrance to the fair at the elevated tracks.
The Official Portrait Photographer's building was built in April adjacent to Arnold's building. The very large (70x200') Accounting building (also referred to as Adminstration & Collections) was  constructed on the corner completely obliterating the view of both photographer's buildings.
These are the only two known photos of Arnold's building. There is no known photo of  the Portrait photographer's building. It is thought that Gibson's bldg. is behind Arnolds, and not in this view. Gibson's was completed April 1893.
According to archives the Arnold building was completed end of Oct,1892.It cost $5,432 and  was paid for by the Exposition Co.
Buildings were measured in man-days of work by Chief Engineer Shankland. Arnold's building was listed as having taken 39 man-days to build.

View of the Accounting bldg. as seen from an almost identical position as that shown above.  [Looking NNW]
John J. Gibson & wife May
ca. 1886 -
Official Portrait Photographer
(J.J. Gibson  1851-1902)

Harlow D. Higinbotham
ca. mid-1880's
(1866 - 1948)
Arnold's Partner in
Official Photographer Concession

Arnold's building is marked "Photo bldg", center -top.
All entrances to the expo were along the western edge of the fair, with the exception of the Midway Plaisance.
North is to the right in this plan.

General map of Exposition.
North is to right.
Fair area is dark. Area above
fair is residental just outside fairgrounds.
Map is from
The Graphic History of the Fair
2nd Ed.,Rev. 1895