Gleanings. 233 
every important change in the weather which has taken place 
since that time. These changes hav^ been found to be as fre- 
quent at every age of the moon as when she has been 7, 14, 21, 
or 28 days old — therefore, she cannot have had the slightest in- 
fluence over any of them." 
Mannite J\Pitrigue. — A paper was communicated to the Paris 
Academy of Science by M. Sobrew, on what he calls mannite 
nitrigue; viz., the substance obtained from manna, honey, &c., 
and treated by nitric acid. The mannite nitrigue or fulminating 
mannite, explodes under the blow of the hammer with the same 
violence as fulminating mercury, and produces in its decomposition 
sufficient heat to ignite gunpowder. M. S. states that he has pre- 
pared capsules, in which instead of fulminating mercury, he 
places a little nitrate mannite crystalized in alcohol, and dis- 
charged a fowling piece with them several times, with the same 
certainty as with the ordinary capsules. 
Asiphalte, Felt Roofing. — Thomas I. Croggin has a patent from 
the English government for asphaltate felt. He describes it as 
principally made of hair, completely saturated with asphalte, with- 
out pitch, tar, or rosin, and consequently more desirable, a good 
non-conductor of heat, entirely impervious to rain, frost and snow, 
and superior to all other descriptions of roofing on account of its 
lightness, elasticity, economy, and durability, because it may be 
laid on by unpractised persons. Its price one penny the super- 
ficial foot, or nine pence the square yard, and it may be manu- 
factured of any required length, 32 inches wide. — Far. and Mech. 
METEOROLOGICAL PHENOMENA. 
1. Rainbow at Midday. — On the 13th of December, at 1 
o'clock, p. M., professor Olmsted observed at Yale College an entire 
rainbow in the north, projected on a dark cloud, the sun mean- 
while shining brightly through a fine misty rain. 
2. Rainbow in the Zenith. — In the month of August or Septem- 
ber last, from 10 to 11 o'clock, a. m.. Rev. Isaac Bird, of Hartford, 
saw a complete circular rainbow in the zenith. The atmosphere 
was a little hazy, but no where so thick as materially to obscure 
the body of the sun. No rain fell. The circle was smaller than 
solar and lunar halos. The colors of the rainbow were distinct. 
3. Aurora Borealis in the Morning. — A brilliant aurora, ac- 
companied by numerous large streamers and auroral waves, was 
seen at this place, (New Haven,) before daylight on the morning 
of Dec. 20th. — Silliman's Journal. 
