_Internal Improvements._--In consequence of the facilities afforded by that part of the great canal which is completed, Plaster of Paris, or Gypsum, which abounds in the western parts of New York, is now selling at Utica at from $1.50 to $2.00 per ton, and it is supposed that any part of that great tract of country lying on the Hudson, may be supplied with it at from 4 to 5 dollars! Onondaga salt will be sold at Albany at from 31 to 37 cents per bushel; and a bushel of wheat, which formerly cost 44 cents to transport it to that city, will be brought there from the interiour, for the small sum of 5 cents. In truth, this canal when finished, will, seemingly, bring the most remote places, even the most distant points of the great lakes, into the neighbourhood of the port of New York. _The Coronation of George IV._ which is to take place August, 1st, is to be conducted on the most economical scale, and is not to cost more than about $450.000!! The price of a coronation dress for a peer and peeress is estimated at about $3.600. _Marriage Promise._--In Somerset county, New Jersey, a young lady lately received the sum of 1250 dollars damages, for a breach of promise of marriage. _Mobile_ is becoming a place of great importance; about 10,000 bales of cotton have been shipped from this port in the present year, and 6,000 remained on hand. This shews an increase of 10,000 bales since last year; and it is calculated that at least 10,000 more will be shipped next year than in the present. _The number of letters_ delivered daily by the post in Paris is, on an average, 32,000; of journals, 18,000. In London, the average of letters is 133,000, and journals 26,000. _Cincinnati, June 15._--On Saturday last, in digging the well of Mr. Wright, near Harrison, in this county, near a mile from White-Water, and about 14 feet from the surface, in a bed of rounded limestone pebbles, a living frog was dug up, which in a short time, hopped away as nimbly as if he had been but a year old. There are trees contiguous, and in lower ground, more than 500 years old, which have evidently taken the places of others of equal growth; so that this frog had probably lain buried for 1000 years. _Mean temperature of the Earth._--According to Laplace, any actual diminution of the mean temperature of the earth would be detected by a diminution of the length of the day.--It appears by computation, that one degree of Fahrenheit's thermometer would make an alteration of nearly one second in the length of a day, and four or five minutes in that of a year. _Heat._--The effect of heat in expanding iron is strongly shown by a gate of that material in this town.--In the cool of the morning it shuts with a considerable spare space, (in the winter perhaps an 8th of an inch) in the middle of a hot day the joints touch, and some force is necessary to close it. The gate is about 3-1/2 feet wide. [_Boston Pal._