Jenny Lind made her British début in London on 7th May 1847 [i] She made a successful tour of the English provinces at the end of the 1847 opera season [ii]
W.H.C. West (the author of Bargery 321, The Rail! The Rail! and Bargery 329 The Railway Footman) wrote a song to which the British Library ascribes a putative date of 1847 called Jenny Lind Mania (British Library shelfmark HS.74/1251.(402.)). The song includes the line "From a toothpick to an omnibus, All are called by her name". Indeed a locomotive class was named after her. [iii]

References;
[i] Oxford Dictionary of National Biography (accessed 06Nov20)
[ii] (Emerson, Isabelle Putnam; Five Centuries of Women Singers (Westport Connecticut, Praeger Publishers, 20050 p155
[iii] http://en.wikipedia.org/wiki/Jenny_Lind_locomotive]

"The panic [caused by the collapse of share prices] culminated in a "Week of Terror," October 17-23, [1847] with multiple banks failing or suspending payments to depositors in the midst of runs."

Reference:
Narron, James and Morgan, Donald P. Crisis Chronicles: Railway Mania, the Hungry Forties, and the Commercial Crisis of 1847 (Liberty Street Economics
https://libertystreeteconomics.newyorkfed.org/2015/06/crisis-chronicles-railway-mania-the-hungry-forties-and-the-commercial-crisis-of-1847.html , accessed 05Nov20)

"With the failed 1846 harvest as prologue, many merchant houses bought corn and other foodstuffs forward, expecting higher prices in the future. By the time these contracts matured in mid-1847, prospects for a strong harvest that summer caused spot prices to fall sharply, catching many speculators short." [i]

                             Wheat Prices and Weekly Wheat Imports, 1844-50 [ii]

References:
[i] Narron, James and Morgan, Donald P. Crisis Chronicles: Railway Mania, the Hungry Forties, and the Commercial Crisis of 1847 (Liberty Street Economics
https://libertystreeteconomics.newyorkfed.org/2015/06/crisis-chronicles-railway-mania-the-hungry-forties-and-the-commercial-crisis-of-1847.html , accessed 05Nov20)
[ii] Campbell, Gareth, "Two Bubbles and a Crisis: Britain in the 1840s" http://www.cliometrics.org/conferences/ASSA/Jan_11/Campbell.pdf.

The District line started in 1864 when the Metropolitan District Railway was created to create an underground 'inner circle' connecting London's railway termini. The first part of the line opened using Metropolitan Railway gas-lit wooden carriages hauled by steam locomotives. The District introduced its own trains in 1871 and was soon extended westwards through Earl's Court to Fulham, Richmond, Ealing and Hounslow. After completing the 'inner circle' and reaching Whitechapel in 1884, it was extended to Upminster in East London in 1902,[i] eight years after the publication of this song.

Reference:
[i] https://en.wikipedia.org/wiki/History_of_the_District_line (accessed 06Nov20)