The almanac for this year tel Is us ;hat ttiere will be a transit of Venus m the oth ot December next, visible throtighout the United States, lt willbe i passing between the sun and ub, of a nearly as large as the earth; aml .-. ii occupy more than a quirter of the ;wenty-four houra in the passing. If the planet were largo onough, or near iiiough to us, it wonld totall? eclipse Lili. 'Che transit oi! Vernis last occurred uu the 8 tb. of December, 1874, and the last one preceding it was in 1769, an ceouut of vvhich, amoug others, was iveii by Uic celebrated Gapl. Cook, vhoobserved il at or near the Sandvicü Islands. Lfter the one of this year, il will ot occur agafn till June 7th, 2004; so of cdiirse, uo one aow living will ïave anothev opportunity of seemg it gain. Astronomers will tnke careul obséivaUuiis o!' it for the parpóse oi aidiug in tke disianotí Lo he sun. In 1874 the different governnents spent over $2,000,000 in the vaious measures necesaary for taking the obaervations, and vet the results were ar frotn satisfactory. Some of the omputations from these observations made the distance to the sun some millions of miles less tb au former esilmates. The distance from the earth to .he sun or to any other heavenly body, ïas never been deünitely ascertained. Jt, is hoped that these observations wil) enable astronomers to flnd this Ustance, and so be able to use it as a meaBuring line for the measurement of he distances betvveen other heavenly bodies. Several points as far from oach other as possible, and favorable for observatiou will be made stations for ,his purpose. Some to be selected will e Cape Horn.Cape of Good Hope, and laces in Australia, and Maciagascar, and some on our own continent. Observatiuuii taken attwo widelyseparated stations at the same instant, will show tbe planet as appearing on differeat portions of the sun's surf ace. These linea oi' observation will of course cross each qther at the planet, forming four of the sides of two long triangles. The base of one of theso triangles will be the line separating the two observers on the earth. The base of the other being on the aan, will be the distanee from where one observer seems to see it, to where the other observer seems to see it on that orb. lf the distanoe befcween the stations be certaiuly known, the obf srvations free from error, and the calculations accurate, they would give the distance to the sun. And for this purpose men possess greater skill, and greater perfection is arrived at in the necessary Instruments than ever bef ore. If the ktiowledge sought be attained tbe sc:iencu of navigatiun wiil thereby be materially advanced. The Western cciatinent, wherever the weather will pèrmit, will be highly favorecí with opportunity for observation. - Mich. Christtan Heald. Dr. Siöuieua has been testing the eiïect of olectricity upon plants. He fouud that by keeping such plants at night under ; continuóos blaze of eleetric üght they Rrew much more rapidly, some, like the fcereals, grew so rapldly as not to arrive at maturity, but in others the size, fiavoi', and coloring of the fruit was iniproved. The resul h of his experiinents seetna to show that nocturnal and winter's rest is unnecesaary lor plants, and that electricity rnay become a valuable ad,i unct to the horticulturist. Major Valentino, the father of Park Valentina who perished with his bride at Spuyten Duyvil, offers for sale the nevv house built and furnished for his son, aud haa decided not to build the extensive additions to his milis ut North Adams, the foundations for which have just boen cooipleted. The Physician and Surgeon contain an analysis for alum of aeventeen S imples of bread by Samuel H. Gun der. Of these samples eleven con tained .ilum, and those from the larg city bakeries showed the most adu teration. Alum was also found in al the "patent" flours.