7 



JOHNSON & ROBINS' 



OFFICE 



OF CONSULTING ENGINEERS, 



AND COUNSELLORS FOR PATENTEES: 



For imparting information on the subject of Inventions, and on the application of 



Chemical and Mechanical Science to the Arts, Agriculture, Manufac- 

 tures, and Mines, and for procuring and defending 



Patents, either in the United States or 



in foreign countries. 



Prof. Walter R. Johnsot*, late of Philadelphia, and Z. C. 

 Robbins. 



of 



Washington City, (to 



m be aided by Hazard 



Knowles, Esq., late Machinist of the United States Patent Of- 

 fice,) have associated themselves together for the prosecution of 

 the above branches of professional business, either in their office, 

 at the Patent Office, or before the courts : and will devote their 



■ » 



undivided attention to forwarding the interests of Inventors or 

 others who may consult them, or place business in their hands. 

 The office of Messrs. J. & R. is on F street, opposite the Patent 

 Office, Washington, D. C, where communications, post-paid, 

 will be promptly attended to ; examinations made, drawings, spe- 

 cifications, and all requisite papers prepared, and models procured 

 when desired, on reasonable terms. Letters of inquiry, expected 

 to be answered after examinations made, must be accompanied 

 by a fee of five dollars. 



Washington, D. C, June 1, 1848. 



[Nov. 1848.— ly] 





