He submits that in order to raise a presumption under section 66( 2) of the Act, in a trial of a person charged with committing an 942 offence under section 66 (1) (b), it must be proved that concentration of alcohol in the blood of the accused person is not less than 0.05 per cent weight in volume, and that can only be proved by the report of the Chemical Examiner or the Medical Officer in the manner provided by section 129B in respect of examination of blood collected in the circumstances and under conditions prescribed by section 129 A. Counsel says that the Legislature having enacted a special provision relating to the procedure by which evidence about concentration of alcohol in blood is to be collected, examined and placed before the Court, no other method of establishing concentration of alcoholic content in the blood of a person charged with an offence under section 66 (1) (b) is permissible, and that even though a concession was made before the Court of Session by counsel appearing for the appellant, evidence aliunde the report under section 129B was inadmissible.