FP comments on timing of original temple garment design.
First Presidency (Joseph F. Smith, Anthon H. Lund, Charles W. Penrose), Letter to Arthur C. Smith, March 10, 1915, in Devery Anderson, The Development of LDS Temple Worship (Salt Lake City: Signature Books, 2011),171
(1). The pattern of the temple garment was given by revelation to the Prophet Joseph Smith [,] exact date as to month or year unknown. (2). the garment with buttons instead of strings, referred to by you, is not the temple garment, and should not be worn as such. (3) It is not right to leave off wearing the temple garment during the day because of hot weather; it should not be taken off at all excepting to be renewed by another, or for the purpose of bathing, or for work or other purposes requiring the baring of the body.