TRACT 38.

PROBLEMS.

333

such accident as that which actually led myself into the trainof thought which soon ended in the complete solution. Theconstruction I first inserted in the Critical Review, as beforementioned in the first volume of these Tracts; next it wasintroduced into my first or quarto volume of Tracts, pub-lished in the year 17S6, accompanied with a short account ofits rise, and a considerable improvement of it, by renderingthe property general for the division into all ratios of parts,equal or unequal, and extending the same to all ellipses, aswell as circles. After which I have usually been in the habitof introducing it into my Dictionary, and the more commonelementary books on mensuration, &c.

Lastly, finding the two constructions introduced, by myfriend Mr. Leslie, the ingenious and learned mathematicalprofessor in the university of Edinburgh, into the first edi-tion of his Geometry, published in 1809, both together inpages 222 and 223 : as these problems were rather of anuncommon nature, I did think some mention might havebeen made of their origin, or the circumstances that have at-tended them; and I hinted as much to my ingenious friend.In consequence of which, probably, I find that the learnedauthor has, in the 2nd edition of his work, separated thosetwo constructions, placing one among the elements at p. 181,and the other among the notes at p. 432, accompanied withthe note, that it was the result of a ‘ principle briefly sug-gested by Mr. Lawson, and afterwards explained and demon-strated in Dr. Hutton’s Mathematical Tracts.’ This changeand announce seemed to make the matter rather worse thanbefore, as it appeared less unfriendly, or less uncivil, to omitnoticing a fact entirely, than to mis-state it. For, certain itis, that Mr. Lawson never suggested any principle or exten-sion, nor any mode of solution whatever; the discoveryhaving been made and published by myself alone.

FINIS.