With regard to the reckoning of longitude, I submit that longitude and time are so intimately related that they may be expressed by a common notation. Longitude is simply the angle formed by two planes passing through the earth's axis, while time is the period occupied by the earth in rotating through that angle. If we adopt the system of measuring time by the revolution of the earth from a recognized zero, one of these planes--that through the zero--may be considered fixed; the other--that through the meridian of the place--being movable, the longitudinal angle is variable. Obviously the variable angle ought to be measured from the fixed plane as zero, and as the motion of the earth by which the equivalent time of the angle is measured is continuous, the longitude ought to be reckoned continuously in one direction. The direction is determined by the notation of the hour meridians, viz., from east to west. If longitude be so reckoned and denoted by the terms used in the notation of cosmic time, the time of day everywhere throughout the globe would invariably denote the precise longitude of the place directly under the mean sun. Conversely, at the epoch of mean solar passage at any place, the longitude being known, cosmic time would be one and the same with the longitude of the place. The advantages of such a system of reckoning and nomenclature, as suggested in the recommendations which I now submit, will be, I think, self-evident. RECOMMENDATIONS FOR THE REGULATION OF TIME AND THE RECKONING OF LONGITUDE 1. _That a system of universal time be established, with the view of facilitating synchronous scientific observations, for chronological reckonings, for the purpose of trade and commerce by sea and land, and for all such uses to which it is applicable._ 2. _That the system be established for the common observance of all peoples, and of such a character that it may be adopted by each separate community, as may be found expedient._ 3. _That the system be based on the principle that for all terrestrial time reckonings there be one recognized unit of measurement only, and that all measured intervals of time be directly related to the one unit measure._ 4. _That the unit measure be the period occupied by the diurnal revolution of the earth, defined by the mean solar passage at the meridian twelve hours from the Prime Meridian established through Greenwich._ 5. _That the unit measure defined as above be held to be a day absolute, and designated a Cosmic Day._ 6. _That such Cosmic Day be held as the chronological date of the earth, changing with the mean solar passage at the anti-meridian of Greenwich._ 7. _That all divisions and multiples of the Cosmic Day be known as Cosmic Time._