“Nearly all the accused had been savagely beaten. Bukharin was spared this but was visibly a broken man. From his prison cell he had written a note to Stalin: 'Koba, why is my death necessary for you?' But Stalin wanted blood. Constantly consulted by Chief Prosecutor Andrei Vyshinski and Vasili Ulrikh at the end of the court's working day, he ordered that the world's press should be convinced of the veracity of the confessions before sentences were passed. Many Western journalists were indeed hoodwinked. The verdict was announced on 13 March: nearly all the defendants were to be shot.
Two days later Stalin approved a further operation to purge 'anti-Soviet elements’. This time he wanted 57,200 people to be arrested across the USSR. Of these, he and Yezhov had agreed, fully 48,000 were to be rapidly tried by troiki and executed. Yezhov, by now practised at the management of such operations, attended to his duties with enthusiasm. Through spring, summer and autumn 1938 the carnage continued as the NKVD meat-grinder performed its grisly task on Stalin's behalf. Having put Yezhov's hand at the controls and ordered him to start the machine, Stalin could keep it running as long as it suited him.
Stalin never saw the Lubyanka cellars. He did not even glimpse the meat-grinder of the operations. Yezhov asked for and received vast resources for his work. He needed more than his executive officials in the NKVD to complete it. The Great Terror required stenographers, guards, executioners, cleaners, torturers, clerks, railwaymen, truck drivers and informers. Lorries marked ‘Meat' or 'Vegetables’ took victims out to rural districts such as Butovo near Moscow where killing fields had been prepared. Trains, often travelling through cities by night, transported Gulag prisoners to the Russian Far North, to Siberia or to Kazakhstan in wagons designed for cattle. The unfortunates were inadequately fed and watered on the journey, and the climate - bitterly cold in the winter and monstrously hot in summer - aggravated the torment. Stalin said he did not want the NKVD's detainees to be given holiday-home treatment. The small comforts that had been available to him in Novaya Uda, Narym, Solvychegodsk or even Kureika were systematically withheld. On arrival in the labour camps they were kept constantly hungry. Yerhov's dieticians had worked out the minimum calorie intake for them to carry out heavy work in timber felling, gold mining or building construction; but the corruption in the Gulag was so general that inmates rarely received their full rations - and Stalin made no recorded effort to discover what conditions were really like for them.
Such was the chaos of the Great Terror that despite Stalin's insistence that each victim should be formally processed by the troiki, the number of arrests and executions has not been ascertained with exactitude. Mayhem precluded such precision. But all the records, different as ther are about details, point in the same general direction. Altogether it would seem that a rough total of one and a half million people were seized by the NKVD in 1937-8. Only around two hundred thousand were eventually released. To be caught in the maw of the NKVD usually meant to face a terrible sentence. The troiki worked hard at their appalling task. The impression got around - or was allowed to get around - that Stalin used nearly all of the arrestees as forced labourers in the Gulag. In fact the NKVD was under instructions to deliver about half of its victims not to the new camps in Siberia or north Russia but to the execution pits outside most cities. Roughly three quarters of a million persons perished under a hail of bullets in that brief period of two years. The Great Terror had its ghastly logic.” - Robert Service, ‘Stalin: A Biography’ (2004) [p. 355 - 356]
