REPORT OF ASSISTANT SECRETARY. 17.") 



esses which are playing so important a part in the pictorial printing of 

 the present time. Photography proper, being a photo-chemical process 

 in which the print is made by the action of the sun's rays, was excluded, 

 the exhibit being limited to those processes in which the printing-press 

 is necessary to the manifolding of the picture, even though the block or 

 plate may have been made wholly or in part by the chemical action of 

 light. The various relief, photo-lithographic, zincographic, calographic, 

 and intaglio processes were grouped separately, and an effort was made 

 to show, by means of prints, the improvement made in each since its 

 discovery ; though, as the processes are usually either wholly or in part 

 secret, no attempt was made to illustrate the methods by which the 

 blocks were produced. Mr. Koehler has prepared a detailed catalogue 

 of the exhibit, in which the various processes are briefly described and 

 much valuable information regarding their history is given. 



I. REVIEW <)F THE EXHIBITS OF THE OTHER DEPARTMENTS OF THE 



GOVERNMENT. 



State Department. — The State Department exhibit was under the di- 

 rection of Mr. llaughwout Howe. It was prepared for the purpose of 

 illustrating the work of that Department. It contained many papers 

 and other objects of great historical interest. The series of diplomatic 

 papers included the letter addressed by Benjamin Franklin to the pre- 

 mier of France in December, 1770 (this being the first official communi- 

 cation ever seut to a foreign court by an officer of our Government) and 

 many other equally interesting papers, among which were letters bear 

 ing the signature of many of the leading sovereigns of the world during 

 the past century, and of almost every one now in power. The original 

 treaty of 17X1* with Great Britain, which secured to us our independence, 

 was exhibited, as were also a number of other treaties with Great Britain, 

 France, The Netherlands, and Turkey, each bearing the seal of its 

 respective government, and a whale's tooth sent asatreaty by the King 

 of the Fiji Islands. There was also a complete series of portraits of 

 the Presidents of the United States, ami another of the Secretaries of 

 State from the time of Jefferson ; also photographs of the principal 

 Government buildings of Washington, and of certain of our foreign 

 offices, with maps showing the locution of our diplomatic and consular 

 stations in all parts of the world. To the above were added many 

 interesting historical relics from the library of the department, scries 

 of medals awarded to the United States, to officers of the Army and 

 Na\ ,\ . and to private citizens, and a full set of the department publica- 

 tions, including I rnited States laws, diplomatic correspondence, foreign 

 relations, consular reports, consular regulations, commercial relations, 

 ami reports on various expositions. 



War Department. — The exhibits of this Department, prepared by 

 Capt. II. A. Russell, Bureau of Ordnance, assisted i>\ Lieut. E. S. 

 I lent on, Third Art i lien . were anion- the most interesting of I he Govern- 



