This paper is a compilation and discussion of all the best determinations of the sun's mean distance and parallax within the last few years, and up to the present time. The comparative weights to be given to the different observations or results are entered into at length, on principles which are stated, and a final mean of the whole is arrived at, giving for the solar parallax 8·″877. This is then compared with the result of the so-called Great Pyramid Sun Distance, which, combined with the best modern determination of the size and shape of the earth, gives a parallax of 8·″876.