Time cabinet

The Time cabinet was an early experimental time machine from the 51st century which used zygma beams.

Origins
The time cabinet was developed by the evil Supreme Alliance. It was an unsuccessful device, as it had been based on Findecker's discovery of the double nexus particle, which, according to the Doctor, went on to lead mankind into a scientific cul-de-sac. It used the principle of a zygma beam, which if overstretched could cause a huge and catastrophic implosion. Its use could lead to severe and life-threatening mutations. It could be locked by fused molecules, and thereafter only opened by a "time key" in the form of its trionic lattice, a unique element which was central to its operation. (DW: The Talons of Weng-Chiang) Another Supreme Alliance war criminal would, however, discover means to reverse the degenerative process. (IDW: The Time Machination)

Usage of the time cabinet
Magnus Greel, the so-called Minister of Justice of the Supreme Alliance, used the experimental device when he was fleeing persecution--or prosecution--as a war criminal, making him (as far as he knew) the first man to travel through time.

Greel arrived in 19th century China, where he had to hide from Imperial soldiers for a long while, and his time cabinet was taken by them. George Litefoot's family got the cabinet as a parting gift from Emperor Tongzhi when they left China in 1873, assuming it was a puzzle box. He never managed to open it. Greel searched for the cabinet for many years, his search eventually leading him to London, where Litefoot had settled after leaving China, and he finally managed to capture the cabinet in 1889. After committing several murders, principally caused by his harvesting the life force of innocents to keep himself together (though in reality this only accelerated the process), he was eventually killed by cellular degeneration when the cabinet could no longer correctly function. The Doctor then destroyed the time key, rendering the time cabinet effectively useless. (DW: The Talons of Weng-Chiang)

Behind the Scenes

 * Dialogue in The Talons of Weng-Chiang said the soldiers taking the cabinet were of Emperor Tongzhi, and thus the beginning of his reign in 1861 can be deduced as an earliest possible arrival date.