NATIONAL MUSEUM BUILDINGS. 205 



1853. 



Mr. Gilbert Cameron was given the contract for completing the 

 structure in accordance with his previous terms, and the building- 

 committee kept constantly in view the idea of rendering the main 

 building entirel}' fireproof and of constructing it in the most durable 

 and substantial manner. These changes of arrangements delayed 

 work until June 13, 1853, from which time onward it was actively 

 prosecuted. The committee found great ditiiculty in deciding upon 

 a proper position and plan of a large lecture room, but finally con- 

 cluded to place it in the second story in the middle of the main build- 

 ing, where the greatest width could be obtained. 



1854. 



At the close of 1851 the building committee reported that the main 

 or center building was finished, with the exception of a few unim- 

 portant additions. Many changes had been required for the better 

 security and adaptation of the building, and they involved an addi- 

 tional expense. 



1855. 



During this year the entire edifice was completed, and the final 

 report of the architect was approved by the committee. The follow- 

 ing account of the interior of the building at this time is taken from 

 Secretary Henry's report for 1855, with some annotations from the 

 report of the building committee: 



The building is at length completed, and its several apartments are now in a c-on- 

 dition to be applied to the uses of the Institution. As various changes have been 

 made in the original plan, the following brief description may not l)e inappropriate at 

 this time. It consists of a main edifice, two wings, two connecting ranges, four large 

 projecting towers, and several smaller ones. Its extreme length from east to west is 

 447 feet, with a breadth varying from 49 feet to 160 feet. The interior of the east 

 wing is separated into two stories, the upper of which is divided into a suite of rooms 

 for the accommodation of the family of the Secretary. The lower story principally 

 comprises a large single room,« at present appropriated to the storage of publications 

 and the reception and distribution of books connected with the system of exchange. 

 The upper story of the easteVn connecting range is divided into a numl)er of small 

 apartments devoted to the operations in natural history, and the lower story is fitted 

 up as a working Ial)oratory. 



The interior of the main edifice is 200 feet long by 50 feet wide^ and consists of 

 two stories and a basement. The upper story is divided into a lecture room capable 

 of holding 2,000 persons '' and into two additional rooms, one on either side, each 50 



« Seventy-five feet by 45 feet. 



*And 60 feet high from the basement floor to the upper ceiling. 



<'The lecture room, the optical and acoustic properties of which are probably 

 unsurpassed by any apartment intended for the same purpose in the United States, 

 occupies one- half of the upper story of the main building, besides a portion of the 

 front and rear towers. Its precise length is 96 feet and extreme width 62 feet. It 

 will comfortably seat 1,500 persons, and when crowded will contain upward of 2,000. 



