Among the Imámíahs it is decided that the Imám _Muhammed, son of Hassan Askery_,[575] is still alive, but concealed from view; they divide the time of his absence into two epochs;[576] namely, “the minor and the greater absence.” The minor absence, which extends to seventy-three years, falls into the time of _Mâtemed Abásí_,[577] in the year of the Hejira 266 (A. D. 879); the greater absence took place in the time of _Rásí_, the son of _Mukteder Abásî_.[578] The distinction between these two epochs is that, during the minor absence, there were a registrar and delegates as intermediates between the pious persons of the religion and the Imáms, whilst, during the greater absence, the appointing and establishing was broken off. The first Vakîl, “delegate, agent,” was _Osman_, son of _Said ul Umrul Asadi_, in the holy place (of Medina); after him, by command of the Imám of the time, his son, _Abu Jâfer_, took charge of the office, which he held about fifty years; after him came _Abu ’l Kásem Hossain Ebn Rúh Ebn Ali Baher Nóubakhtí_, who bequeathed his place to _Abu’l-Hasan Alî Ebn Muhammed Samírí_, and this was the last Vakíl. When he was sick, the Shíâhs asked him: “Who shall after thee be the Vakíl of the holy place?” He wrote his command by a last will, by which he abolished the charge, and the command is as follows: In the name of the bountiful and merciful God: O Ali, son of Muhammed Samiri, may God increase the recompense of thy brothers with regard to thee, for thou art dead, and between thee and me there are six days;[579] therefore arrange thy affairs, and propose to nobody to fill thy place after thy death; certainly the complete absence is now accomplished, and no further manifestation shall take place but after the permission of God, the most high. He mentioned it, and this after a long delay, and the obduracy of hearts, and after the filling of the earth with violence. And there shall come from among my people one to be a witness; but he who desires it before the coming forth of a Safiani and the Sihat, he is a deceiver, and ought to be avoided. There is no power and no strength but one God, the most high and most great. Abul-Hasan died in the middle of Shâbán (the eighth month of the year), in the year of the Hejira 328 (A. D. 939). It is to be known, that the tradition among the Shiâhs of the _Imámiyat-âsulín_ sect is divided into four parts: _sáhíh_, “authentic;” _hasen_, “elegant;” _músik_, “strong;” and _sâíf_, “weak.” An _hadís sahih_, “an authentic tradition,” is one, the authority of which goes back to _mâsúm_,[580] according to the narration of an _âdil Imám_, “a just Imám,” in the description of whom the _árbáb-i-hadis_, “the masters of history,” have used the word _âdil_, whether the narrator be one person, or whether there be more than one, provided in the description of them all the same language has been used.