The Arkansaw traveler., 1884-12-20
C0MpiLtd fer T3< Ar&ans4w TSevelev.
 SCIENTIFIC MISCELLANY.

iouno 10 pc prevfous to sewer gas. Painting is recommended.
 It has been proven to the French As- sociation for the Advancement of Science that the surgical opeI ation of trepanaing was Practiced iA prehistoric ages.
 Dr. Sephus Tromholt, of Norway, is about preparing catalogue of all the au- roras which have been observed in Northern Europe from the earliest times.
 The re-plauting of forests in north western India has already made itself bene- hcially felt according to Sir G. Birdwood, in increasing the rainfall of various districts.
 The deep sea cTustacea, according to Prot. Moseley, either have very large eyes or are eyeless and there must be a source of light in the deep sea That source, he claims, is Phosphoresenc@, but its light mus, be very dim.
 The little living worms which have been most unexpe ctedly discovered in ice are described by Prof. Leidy as being white or colorless, and from one-fourth to one sixth of an inch long by one-seventy fifth of
 
 known.
 A Swedish naturalist, Dr. Wills, has investigated the strength of various kinds of sea weed to re ist strains, such as are caused by the swell of the sea. He finds that sea. weeds are very strong and elastic, the parts which ordinarily lie lowest in the water being capable of bearing the greatest strain.
 According to Sir Trevor Lawrence, M. P, there is a collector of orchids in England who employs fourteen persons-nearly all German naturalists, and each costing abou, $6 900 year---to search for different species and varieties in different parts of the world. He has two acres of the plants under glass, and his total annual expenditure on orchids is nearly $Iooooo.
 To prove that pr. Koch's "comma bacillus is not the cause of cholera, and that the vomit of cholera patients is not in fectious, French physician has swallowed some pills made f. om the vsmit of person who died from cholera. He was only slightly affected if at all, but two guinea pigs and dog which were inoculated with th . same vomit succumbed at once.
 A source of pure water.-In a commu. nication to the French Academy of Science, Mons. A. H. de Villeneuve has urged the inn portance of using distilled water for drinking purposes, and has suggested that the cost may be greatly reduced by using that obtain able from steam engines. He asserts that it is not unr alatable and contains sufficient air, while the absence of lime salts is an advan- tage.
 Protected Soil-A German experi- menter, Prof. E. Wollny, has found that soil covered with living herbage or dead vege- table matter is colder in summer and warmer in winter than bare soil under otk erwise sim liar conditions. The difference of tempera- ture IS greatest in summer and least in spring and autumn. Bare soil heats more quickly Tn the spring and cools more quickly in au- tumn than that covered with living or dead vegetable matter.
 Roots Turned Aside by Gases.-It has been demonstrated b, Dr. Hans Molisch that the roots of plants may be defected from their normal direction by exposure on one side to certain gases. If such gases are in moderate quantities the roots bend away from their source; if in larger quantities, to- ward such source. The side of the root ex- posed to the action of the gas grows more strongly than the other.
 Earthquake Velocities.-ln experiments by Pfefs. Milne and Gray it has been de- termined that normal earthquake waves are anSmffAd fhrnnCh harIanaA .L~ rate of 437 feet per second, and transverse waves at 357 feet per second. Mallet's earlier experiments showed that earthquakes traverse sand at a speed of s3s feet, jointed granite I. .3o6 feet, and solid granite I,665 feet per second. Pref. Ewing considers the las, number to be very much too small.
 Mushroom Poisoning.-During last summer fifteen persons were killed in France by eating fungi which wete believed to be the edible mushroom. T4e fungus eaten in some of the cases was of a kind which is CT dinarily wholesome, but which develops pois- onous qualities under certain conditions. In cooking common test for poison is a piece of silver, which theory asserts will become blackened when placed in the vessel contain
 
 has proven to be unreliable, as in several of these French cases it was applied and the silver remained unaffected while the mush- rooms killed those who ate them.
 The Dissolving Continents the vast quantities of solid particles which are washed from the land into the scare ducing the height of the entire Mississippi basin at the estimated rate of one foot in 6,ooo years-much matter is dissolved by the water. and carried away in a state in which it ordinarily escapes notice. From data furnished by the Mississippi, the La Plata, the Amazon and the St Lawrence, Mir. T. Mellard Reade. an English geologist who has devoted much attention to the chemical denudation of the earth's surface, has caicu- lated that the whole American continent is losing in this way an average of 100 tons per square mile each year. Similar results have