Human skin, hair and iron filings - the cocktail of what you are breathing in on the tube.
There were other passengers in the carriage at the time. Police want to trace the man seen in this e-fit.
Parts of the Tube have turned into an American-style metro on one of the world's most popular digital maps.
The planned three-day strike by London Underground workers has been suspended, the RMT Union has said.
The London Underground and Rail, Maritime and Transport are holding last-ditch talks just hours before a three day strike, that could affect millions of people across London and surrounding areas.
Conciliation service Acas said the talks between the RMT and London Underground started at 10am.
RMT union members are set to walk out of their jobs for three days at 9pm this evening, in a long-running dispute with the London Underground over ticket office closures.
A two-day strike last week caused huge disruption, with roads clogged as people switched to other forms of transport.
London Underground workers are to begin three days of strike action in the long-running row over ticket office closures.
Members of the Rail, Maritime and Transport (RMT) union will walk out from 9pm.
The union claimed that long-running talks hosted by the conciliation service Acas, aimed at settling the dispute were "wrecked by a combination of management intransigence and the introduction of additional measures" the union said worsened the original plans.
Passengers will gain access to WiFi at six more London Underground stations, Transport for London has revealed.
A partnership between Transport for London and Virgin Media has led to the installation of WiFi at more than 100 stations already in the capital.
Commuters at Golders Green, Southgate, West Kensington, Parsons Green, Kilburn and East Putney will be able to access their emails and social media even when on platforms and in the absence of mobile phone coverage.
Virgin Media said more than 800,000 devices have connected to the networks so far as customers take advantage of a deal between the major UK mobile networks, including EE, O2 and Vodafone, meaning that users of those services can connect to the WiFi at no extra cost.
TfL announced earlier this week that commuters will be able to use smartphones to pay for Tube travel by the end of the year in the latest technological development in the capital.
The Oyster card will remain as a ticketing option for rail customers despite the introduction of smartphone payments later this year, Transport for London has told ITV London.
Mobile phones with a payment app will be able to open ticket barriers across London's rail network from later this year, but TfL insist there are no plans to withdraw the Oyster.
"Oyster operates alongside contactless on the buses and will do so on the Tube and rail network too," a spokesperson said.
Transport for London said it is aiming to make it easier for customers to travel on the Tube by introducing smartphone payments on the service.
Shashi Verma, TfL’s Director of Customer Experience, said:
We are continuing to modernise all our transport services to make it easier for customers to do business with us.
The upgrade to our readers to accept contactless payment cards also makes them capable of accepting suitable payment applications on mobile phones.
We are testing to see how the devices perform on the system and welcome any innovations which improve the services and choices we are able to offer customers.
Tube passengers will be able to pay for their travel using smartphones by the end of the year, Transport for London has confirmed.
Mobile phones with a payment app will be able to open ticket barriers across the Underground network.
Transport for London said staff, stakeholders and selected members of the public were currently testing the system ahead of the launch to the general public later this year.
Contactless payment was launched on London's buses in December 2012 and more than 11.5 million journeys have been made using the payment option.
It was announced earlier this month that commuters will no longer be able to pay using cash on London buses from Sunday July 6.
Commuters endured a difficult return to work after the Easter break as delays affected six Underground lines this morning.
The Piccadilly Line suffered severe delays after signal failures at King's Cross and Ealing Common while a faulty train affected services on the Jubilee Line.
Commuters also reported queues at Waterloo station as a result of the delays.
Signal problems near Finchley Road also led to delays to trains on the Metropolitan, Hammersmith & City and Circle lines.
Passengers will face further disruption from tomorrow as a result of the modernisation of Bond Street station with Central Line trains not stopping there until late June.
No service btn Piccadilly Circus and Elephant & Castle and Severe delays on rest of line while we fix a faulty train at Lambeth North.
Severe delays are occurring on the entire line due to an earlier faulty train