Belzec was the first camp devoted exclusively to extermination and therefore the model for all subsequent such camps.  The gassings conducted there were intended as experiments that would establish which methods might be most efficient for killing large numbers of human beings.  As Zyklon B had not yet been developed, the gas used at Belzec was carbon monoxide engine exhaust.  The Nazis attempted, however, to keep the Jews (who were arriving in packed boxcars) unaware of their fate until the moment it overtook them.  Deceit was the order of the day, with an elaborate masquerade devised to fool the victims.  Arad offers the following testimony by SS Scharfuhrer Erich Fuchs, from the trial of SS Oberscharfuhrer Josef Oberhauser, the officer who was in charge of the construction of Belzec:

                                I heard with my own ears how Wirth, in a quite convincing voice,
                        explained to the Jews that they would be deported further and before
                        that, for hygienic reasons, they must bathe themselves and their
                        clothes would have to be disinfected.  Inside the undressing barrack
                        was a counter for the deposit of valuables.  It was made clear to the
                        Jews that after the bath their valuables would be returned to them.  I
                        can still hear, until today, how the Jews applauded Wirth after his
                        speech.  This behavior of the Jews convinces me that the Jews believed
                        Wirth . . .
                                                                                                                page 70
 

        The following account of a gassing at Belzec is from Obersturmfuhrer Kurt Gerstein, who visited the camps to advise on how to disinfect the clothes of murdered Jews.

                           . . . the march began.  To the left and right, barbed wire; behind;
                            two dozen Ukrainians, guns in hand.
                                    They approached.  Wirth and I were standing on the ramp in
                            front of the death chambers.  Completely nude men, women, young
                            girls, children, babies, cripples, filed by.  At the corner stood a heavy
                            SS man, who told the poor people, in a pastoral voice:  'No harm will
                            come to you.  You just have to breathe very deeply, that strengthens
                            the lungs, inhaling is a means of preventing contagious diseases. It's
                            a good disinfection!'  They asked what was going to happen to them.
                            He told them:  'The men will have to work, building roads and houses.
                            But the women won't be obliged to do so; they'll do housework,
                            cooking.'  For some of these poor creatures, this was a last small hope,
                            enough to carry them, unresisting, as far as the death chambers. . . .
                                    . . . Unterscharfuhrer Hackenholt was making great efforts to get
                            the engine running.  But it doesn't go.  Captain Wirth comes up.  I can
                            see he is afraid because I am present at a disaster.  Yes, I see it all
                            and I wait.  My stopwatch showed it all, 50 minutes, 70 minutes, and
                            the diesel did not start.  The people wait inside the gas chambers.  In
                            vain.  They can be heard weeping. . . .  Furious, Captain Wirth lashes
                            the Ukrainian assisting Hackenholt twelve, thirteen times, in the face.
                            After 2 hours and 49 minutes--the stopwatch recorded it all--the diesel
                            started.  Up to that moment, the people shut up in those four crowded
                            chambers were still alive, four times 750 persons in four times 45 cubic
                            meters.  Another 25 minutes elapsed.  Many were already dead, that
                            could be seen through the small window because an electric lamp
                            inside lit up the chamber for a few moments.  After 28 minutes, only a
                            few were still alive.  Finally, after 32 minutes, all were dead. . . .
                                    . . . Two dozen workers were busy checking the mouths of the
                            dead, which they opened with iron hooks.  "Gold to the left, without
                            gold to the right!' . . . Dentists hammered out gold teeth, bridges and
                            crowns.  In the midst of them stood Captain Wirth.  He was in his
                            element, and showing me a large can full of teeth, he said:  'See for
                            yourself the weight of that gold!  It's only from yesterday and the day
                            before.  You can't imagine what we find every day--dollars, diamonds,
                            gold.  You'll see for yourself! . . .'
                                                                                                               pages 101-102
 

        In the epilogue to his book, Arad makes the point that although the victims deported to Belzec--as well as Sobibor and Treblinka-- were unaware of the fate that awaited them, information about what was happening in the extermination camps did reach the governments of Great Britain and the United States and probably also the Soviet Union.  "No action followed this information," writes Arad on page 379:

                            No steps were taken to warn the victims, to call on the local population
                            and Underground to help the victims, to bomb the railways, or even the
                            camps, to disturb the smooth implementation of the deportations and
                            extermination.  The Jewish people were left to their fate.