The Tiffany dynasty was founded in 1837 at 259 Broadway in New York City by Charles Louis Tiffany and partner John B Young. In 1847 they expanded and moved to 271 Broadway, it is here that American made silver finally took its place alongside the Tiffany name. John C Moore a very talented local siversmith played a major role in this development. The firm moved yet again in 1853, to larger quarters at 550 Broadway and the name was changed to that of which it is known today Tiffany & Co. In 1867, they exhibited at the Exposition Universelle in Paris, where Tiffany became the first American firm to win an award for excellence in silver. In 1868 Charles L. Tiffany amalgamated with the Silversmith firm Edward C. Moore ( Johns son ) and consequently became a manufacturer of silver as well as a retailer.By the time Edward C. Moores death in 1891, Tiffany & Co. had won major awards at  successive European and American Expositions and had become the most internationally respected American silver manufacturer. The founder Charles L. Tiffany passed away in 1902. Tiffany &  Co. moved to its present premises at 5th. Avenue in 1940 and remained in the hands of Tiffany and Moore  families until 1955. Tiffany & Co. continues the legacy of producing some of the worlds finest designs and quality in silver. 

Conclusion: Looking from top to bottom.

1) The name Tiffany & Co. is the logo since 1853 to this present day.

2) 700 is the pattern number. 1856 pattern nr. 301 - 1860 pattern nr. 1001.

3) In 1851 seeking to give their silver goods distinction, Tiffany became the first American firm to use the English Sterling 925/1000.

4) 8686 is the order number.

5) In 1853 Tiffany moved to 550 Broadway.

6) The 2 x Ms on either side is the signature of John C. Moore between 1854 - 1869.

Summary:

This hallmark shows that this piece of silver was made by Tiffany & Co. crafted by the silversmith John C. Moore in Sterling at the premises 550 Broadway, New York City , between the dates of 1854 - 1869.