June, igo6.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



459 



of Botany, lias some iiUcrcsiting notes on eleven new or 

 crilical species of Britisli marine algae. Two of tlicsc were 

 previously unl^nown, and tlirce more belonj^ to g^encra not 

 previously recorded as British. Most of the species are 

 minute, of the two new species, one, TJlplocohm Codii, grows 

 between the cortical cells of another alga, Codium tomento- 

 niim. The other new species is named Me.wqlnia neqlecta, 

 which has probably been previously passed over as 

 Mi'siioliiia Griff iihsiana, which it superficially much 

 resembles, but is distinguished by the mucli shorter cortical 

 filaments and larger spores. 



CHEMICAL. 



By C. AiNswoKTH MiTCHELi., I!. A. (Oxon.), F.I.C. 



The Action of Radium on Precious 

 Stones. 



ExPERlMEMTs made by Herr Miethe have shown that many 

 precious stones are changed in colour when expofcd for some 

 time to the action of radium rays. Thus a colourless diamond 

 from Borneo became pale yellow after eight days' exposure 

 to the rays of an impure radium bromide, and the colour 

 became much darker after another eight days. Heating the 

 stone to redness reduced but did not destroy the yellow 

 coloration. In the case of a sapphire, the light blue colour 

 changed to green after two hours' exposure to the rays, then 

 yellow, reddish yellow, and, finally, after 14 days, yellowish- 

 brown. The colour disappeared on heating the sapphire, but 

 a light yellow tint invariably re-appeared when the stone 

 became cold. The rays did not affect the colour of the 

 amethyst, ruby, blue topaz, or chrysoberyl ; but a tourmaline 

 with a green end became green at any other part on which 

 the rays were allowed to act. 



Philippine Wood Oils. 



Fluid resins closely resembling balsams in composition and 

 characteristics are in common use as varnishes throughout 

 the Philippine Islands, and the best known of these have 

 recently been examined by Mr. A. M. Clover. Oil of supa is 

 obtained from Sindora Wallichii, a tree widely distributed 

 throughout the Islands. The oil, of which about ton litres are 

 collected from each tree, is a mobile pale yellow liquid, which 

 rapidly becomes dark and viscous on contact with the air, and 

 slowly dries to a hard film when spread in a thin layer. In cer- 

 tain districts it is also used as a lamp oil. A similar product 

 known as balao, or oil of apitoni;, is collected by cutting cup- 

 shaped cavities in the apitong tree. It is white when fresh, 

 but rapidly darkens on exposure to the air, and spread in thin 

 films forms a very tough varnish. It is superior to supa oil in 

 its drying properties, and also differs from it in becoming solid 

 on contact with steam. Malapaho, or oil of panoo is a colour- 

 less product, obtained from the tree Diptcrocarpiis vernicijluus 

 by the same method. It dries but slowly on exposure to the 

 air, and is thus not used to the same extent as balao or snpa 

 oil. It also differs from the former in becoming more mobile 

 under the influence of steam. Chemicall)', all these wood 

 oils consist almost entirely of the hydrocarbons known as 

 sesquiterpenes. They are more or less volatile in a current of 

 steam, and are quite distinct from the ordinary drying veget- 

 able fixed oils, such as linseed or walnut oils, which consist of 

 compounds of glycerin with different fatty acids. 



Trachinus Venom. 



It had long been suspected that the poison glands of the 

 greater wcever (Triichiiius draco) contained a definite toxine, 

 but it was not until 190; that this was shown by M. Briot to 

 be the case. He obtained poisonous solutions possessing the 

 characteristic properties of true toxinesby extracting the gland 

 with glycerin containing chloroform, but did not isolate the 

 poison in anything approaching a state of purity. The work 

 lh,at has been done on the subject is reviewed by Dr. Oppen- 

 hcimer in " Toxine und Antitoxine," an Knglish edition of 

 which is now annour,ced. The toxine has a direct action upon 

 the heart and causes convulsions and paralysis, the latter being 

 a characteristic symptom. It is destroyed bv being heated 

 for 30 minutes at 212' 1". and by calcium cMoride and gold 

 chloride. In addition to its toxic function trachinus venom 



resembles snake venom in having a haemolytic function, i.e., 

 the power of dissolving the red corpuscles of the blood. This 

 lysine in the venom is destroyed when heated for about 20 

 minutes at 212" P.. and is thus less stable than the toxic 

 principal. The normal serum of the horse contains an anti- 

 hxmolysine against trachinus lysine, just as it does against 

 the h.-emolysine of snake venoms. Trachinus venom, how- 

 ever, is quite distinct from snake venom, for it acts in quite a 

 different manner, and a serum rendered antitoxic to snake 

 venom has no effect upon either the toxic or ha^molytic func- 

 tion of trachinus venom. It is possible to produce a certain 

 degree of immunity to the venom in rabbits by cautious in- 

 jection of a diluted venom, and the serum of the treated 

 animal then contains a specific antitoxine, which, however, does 

 not invariably afford protection against the local effects of the 

 poison. The venom of Trachinus vipera is very similar to that 

 of T. draco, as regards its effect upon guinea pigs, but has 

 much less action upon rabbits. Several other fish, e.g., the 

 lamprey, appear to contain poisons which act as definite 

 toxines, but these have not yet been investigated. The venom 

 of the poisonous Japanese Tetrodoii iju^u) and of certain other 

 fish, appear to contain poisonous compounds of the nature of 

 substituted ammonias rather than true toxines, i.e., unstable 

 specific poisons capable of producing specific antitoxines in 

 the serum of an animal. 



GEOLOGICAL. 



By Edward A. Martin, F.G.S. 



The Great Californian Earthquake. 



The stoppage of the fires of N'esuvius has been signalised 

 by a great earthquake which has laid San Francisco in 

 ruins, and has resulted in a devastation such as has been 

 unknown in any civilised territory during the present 

 generation of mankind. \\'as there any connection between 

 the one and the other, is a question which will at once be 

 asked. The greatest caution must be exercised before 

 giving an answer. If merely a coincidence, it is a remark- 

 able one. It is certain that an enormous vacuity must have 

 been formed in the place which fed the eruption from 

 Vesuvius. Other material must have flowed in from 

 regions around, and stupendous underground movements 

 of the kind would have equivalent results. The result 

 might be a caving-in, through lack of support, of some spot 

 of weakness in the earth's crust, and the formation of one 

 or more groat faults. The shock or shocks which would 

 be given rise to w'ould travel in every direction, and when 

 Lhey reached the surface of the earth the effect would be 

 disastrous. Possibly secondary shocks would follow later 

 from refraction or rellection from the earth's central core. 

 To some such causes the present earthquake is attributable, 

 and in this connection it is well to remember that the great 

 Charlestown earthquake followed (ho closing of the great 

 cralor of Kilauea, in the S;uidwich Isl.ands." 



Some Details of the Recent Eruption. 



While the receiil W.suvian outbur^t was fresh in the 

 [Jublic mind, Professor (juiseppe de Lorenzo contributed a 

 paper to the proceedings of the Geological Societv, which 

 lie wrote while yet the decrescent phase of the eruption 

 was being pursued. The maximum outburst took place 

 during the night of April 7-8, and blew 3,000 f<ct into 

 the air, scoria; and lapilli of lava, with fragments derived 

 from the wreckage of the cone. A south-westerly wind 

 swept the ash, it appears, across the Adriatic, into Monte- 

 negro, whilst the lava flowed south and south-west through 

 ail enormous fissure in the old rim of the crater. On .April 

 the 9tli and lolh, the wind had changed to the north-east, 

 and when the collapse of the cone of the principal crater 

 occurred, it was accompanied, or rapidiv followed, bv the 

 ejection of steam and ilust to a height of 22,000 to 26,000 

 feet. This changed the direction in which the dust was 

 carried, and it now reached the shores of Spain ; but on the 

 nth the cloud was impelled northward. On the 13111 the 

 gi.mt cone was found to have a horizontal rim very little 

 higher than Monte Somma, and with n crater about 1,000 

 fi( 1 in di.imeter, the cone being almost snow-white from the 

 deposit of sublimates. .Asphyxiation caused manv deaths, 



