It seems to me, therefore, that an examination of the legislation, and a consideration of authority at present binding on us, warrant the formulation of a general rule about the operation and effect of s.47i which may be thus expressed: Where an attempt is made to tender evidence of the blood alcohol content of a patient based upon a sample of blood taken, preserved, and analysed, in consequence of acts done, or purported or claimed to have been done, in pursuance of s.47i, the Court must determine, in each particular case, how the rules of evidence governing relevance and admissibility ought to be applied to the special subject matter. For that purpose those rules of evidence should first be identified and formulated, and the question should then be asked: How should those rules operate on and with respect to the evidence tendered, having regard to the effects of any non-compliance with s.47i in the particular circumstances of the case? No general rule - a fortiori, no rule of thumb - can be enunciated that is capable of being indiscriminately applied; in every case, the sample, its history, the results of its analysis, and the requirements of s.47i, are simply elements in a complex of material which the trial Judge must assess in order to apply the apposite rules of evidence."