M.M.White undertaker WashingtonDC Matthias M. White undertaker of Washington , DC Fisk and Raymond metallic coffins

Fanny was youngest child of -- Baron Adolph Wilhelm August Friedrich von Steinwehr (September 25, 1822 – February 25, 1877) was a German-Brunswick army officer who emigrated to the United States, became a geographer, cartographer, and author, and served as a Union general in the American Civil War.

 Fanny died Sunday October 26th at Fairfax County Court House and must have been brought from Virginia to DC to be embalmed before being sent to Albany NY

Union soldiers in front of Court House 1862

Lots more can be found out about this family here ; Family Search

I like to highlight known burials by MM White this one is August 1857 at Congressional Cemetery

Commodore John Thomas Newton (May 20, 1793 – July 28, 1857) was an officer in the United States Navy who commanded several ships over a period of decades, undertaking missions in the Caribbean and leading the first crossing of the Atlantic by an American steam-powered warship. He was court-martialed following a fire that destroyed that vessel, but his suspension from service was remitted by President John Tyler, after which Newton commanded Pensacola Navy Yard and the Home Squadron for periods. He died while serving in his last post as president of a Naval Court of Inquiry. 

Death 

Newton died on July 28, 1857, in Washington, D.C., at age 64, of apoplexy, while visiting the residence of Charles Winder.[1] The Brooklyn Daily Eagle reported at the time of his death that Newton "considered Brooklyn as his home", and that he "had a large circle of relatives and friends in this city".[35] The Washington Evening Star reported that it had "stopped the press" with their edition of the day half-worked off to add the announcement of his death.[1] Volunteer companies of the District of Columbia were ordered to attend his funeral.[1] The members of the three Naval Courts of Inquiry met thereafter and appointed a committee to draft resolutions commemorating Newton, which were published in The Washington Union and transmitted to Newton's family.[34] He was buried at the Congressional Cemetery. Burning of the USS Missouri