The efficiency of this exercise in communicating knowledge, was equally conspicuous in another experiment, conducted under the eye of the Principal, Professors, and Clergymen of Aberdeen, in July 1828. The persons on whom this experiment was made, were children taken from the lower classes of society, carefully selected on two several days, by a committee of clergymen appointed for the purpose, from the various schools in the city. These children were all carefully and individually examined in private by the committee, and were chosen from among their companions, not on account of their natural abilities, or educational acquirements, but specially and simply on account of their ignorance. The precautions taken by the Rev. and learned examinators, to secure accuracy in their ultimate decision, were at once judicious and complete; and were intended to enable them to say with confidence at the close of the experiment, that the results, whatever they might be, were really the effects of the exercise and discipline to which the children during it had been subjected, and were in no respect due to the previous capacity or the attainments of the children. To secure this important preliminary object, therefore, the sub-committee of clergymen above alluded to was appointed, as soon as the experiment was determined upon, with instructions to collect a class of the most ignorant children they could find, attending the several schools, and who it was thought would be, of course, most incapacitated for receiving instruction. This sub-committee, consisting of the Rev. John Murray, the Rev. Abercromby L. Gordon, and the Rev. David Simpson, in their previous Report, say, "We, on two several days, met with the children which were collected from the various schools, and examined them individually, and apart from each other; avoiding every appearance of formality, and endeavouring to draw them into familiar conversation, that we might correctly ascertain the state of their religious knowledge on the three following points, which we considered to be the best criterion by which to judge of their understanding of the other less important points in the gospel scheme of salvation.--These points were, 1. Our connection, as sinners, with Adam; 2. Our connection with Christ as the Saviour; 3. The means by which we become interested in the salvation of Christ. On minutely examining each child on these points, one by one, and endeavouring, by varied and familiar language and cross-questioning, without confusing their ideas, to ascertain the knowledge which they possessed on these first principles, we accurately, and at the time, minuted the result, distinguishing those points which they understood, and those which they did not. From this list we afterwards selected twenty-two names, of children who appeared from the list, to be the most ignorant, by _not having any marks of approval on any one of these points_ on which they were examined;--although delicacy