REPORT ON THE SECTION OF PHYSICAL APPARATUS 

 IN THE U. S. NATIONAL MUSEUM, 1891. 



By W. C. WiNLOCK, Houorari/ Curator. 



The collectiou of physical apparatus, cousistiug chiefly of pieces pro- 

 cured by Prof. Heury for researches iu electricity and sound, was stored, 

 when first placed in my charge, in the laboratory rooms on the third 

 story of the east wing of the Smithsonian Institution. In April, 1890, 

 all of the apparatus was placed, by the direction of the Secretary, though 

 without much systematic arrangement, in cases in the south entrance 

 of the building. 



The pressure of other official duties has prevented me from devoting 

 the time necessary to catalogue this apparatus in a thorough manner, 

 though some progress has been made in laying out the work, and it is 

 hoped that an opportunity will soon be found to separate the pieces 

 that are of interest as Museum specimens from those that should be 

 placed in storage. 



A careful distinction is made between the apparatus which is intended 

 for exhibition and that purchased for use in connection with the astro- 

 physical observatory and for other experimental purposes. 



The curator hopes that with a little clerical assistance it will be pos- 

 sible to draw up a complete inventory of all the apparatus under his 

 care. 



The principal accessions to the Museum apparatus are a collection of 

 ancient watch movements, made by the Secretary, Mr. S. P. Langley, 

 during a visit to London and Paris in the summer of 1890. These have 

 been labeled and exhibited, together with several ancient dials and an 

 interesting astrolabe, under the immediate care of Prof. Mason. Prof. 

 Mason has added a few watches that have been held in his own depart 

 ment. 



A collection of old surveying instruments has been received from the 

 surveyor-general of Florida through the Department of the Interior. It 

 is supposed that these instruments were used by Andrew Ellicott, esq., 

 the commissioner, on the part of the United States, in laying theboundary 

 line between Florida and Georgia in the year 1795 in conjunction with 

 the Spanish commissioner, Capt. Minot. 



A set of bronze weights and the works of an ancient clock, purchased 

 in Spain at the request of Secretary Langley by Col. F. A. Seely, of the 

 United States Patent Office, have also been received. 



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