Washington Apr. 21. 05.
I recieved yesterday your favor of the 10th. with the meteorological chart inclosed. it is one of the several ingenious representations which the linear mode has enabled us to make, & is much more satisfactory to the eye than numbers. there is another species of meteorological table which I have seen suggested somewhere & have often wished I had time & materials to form. for the Maritime states of N. America for instance, from Florida to Canada inclusive, draw first a vertical column for the months & their days; and a line across the paper for every day of the year. make a 2d. column for the flowering, leafing, fruiting, falling of different kinds of trees & other vegetables, the appearance & disappearance of birds, reptiles, insects, frost, ice, & whatever indicates the progress of season. then add a column for each of the states on the sea coast from South to North and extend a line from each phenomenon noted in the 2d. column, horizontally or rather obliquely through each state column on the day on which that phenomenon appeared there. this would give the most perfect idea possible of the advance of the season from South to North & it’s recess in Autumn. but to procure the materials should require a careful observer at every degree at least from 25.° to 50.° of latitude. it would then be curious to make a similar one on any given parallel of latitude, say 37½° (as a middle term) from East to West, in order to ascertain the effect of the elevation & depression of the country on the progress of the seasons. the effect we know to be very great. the Maryland & Virginia line on the Eastern shore for instance is within a few minutes of the latitude of Monticello. but I imagine their season is 10. days or a fortnight ahead of mine. Accept my friendly salutations.
DLC: Papers of Thomas Jefferson.