Upvote:4
It appears that Heinrich Weber's grave is no longer extant. The city archives of Strasbourg provide an online archive of burial records that include those from the year 1913. We find Weber in the list of burials for the Cimetière Saint-Louis, Strasbourg, protestant section, 1893-1957, p. 80 (p. 83 of the scan):
Entry No. 1818. Weber Heinrich Prof. Age 70. Address: Taulerring 33. Date of death: May 17. Date of burial: May 19. Location of grave: division 2, row 3, grave no. 15. Lease expiration: September 30, 1968
The personal data from the entry agrees (with exception of the age of the deceased) with a death notice for Heinrich Weber published in a local newspaper: Straßburger Post, Sunday, May 18, 1913, No. 554, morning edition / second sheet:
Heute Morgen um 6 Uhr verschied an den Folgen eines Schlaganfalls nach kurzer Krankheit unser lieber Vater, Schwiegervater und Großvater,
Professor
Dr. Heinrich Weberim 72. Lebensjahr.
Straßburg i. E., den 17. Mai 1913.
Prof. Dr. Rudolf H. Weber, Rostock
Dr. med Richard Weber, Weißenburg i. E.
Ida Weber
Anna Weber
Helene Weber, geb. Bauer, Rostock
Anna Weber, geb. Nöldeke, Weißenburg i. E.
und vier EnkelkinderDie Beerdigung findet Montag, den 19. Mai um 3 Uhr vom Hause, Taulerring 33 aus statt.
This tells us that Heinrich Weber died from a stroke at 6am on May 17 (Saturday), and that his funeral was set for May 19 (Monday), with funeral proceedings starting at 3pm at his residence at Taulerring 33 (today: 33 Boulevard Tauler).
For a detailed obituary see: A. Voss, "Heinrich Weber", Jahresbericht der Deutschen Mathematiker-Vereinigung, Vol. 23, Leipzig: B. G. Teubner 1914, pp. 431-444 (scan online)