l62 



NA TURE 



WJan. I, 1874 



forgus has a season of rest underground, and whether in the 

 condition of resting spores, a sclerotioid mass or a number of niy- 

 celioid threads, the principal fact remains that the fungus lives 

 through the winter in a state of rest. As to certain potatoes 

 being able to resist the disease, I shall shortly be able to show 

 that whilst certain breeds of potatoes entirely resist it in one 

 place, they fall a nady prey to it in another. 



Mcnce any experiments carried on in one place by one person, 

 though valuable in themselves, must be inconclusive and im- 

 perfect. 



The great question is, " How can the disease be evaded or 

 destroyed?" and this can only be answered, if answered at all, 

 by men who thoroughly know the fungus and its allies. 



WORTHINGTON G. SMITH 



The Denudation of Limestone Hills of Saravi'ak 



There is an agency in the denudation of the limestone rocks 

 of Sarawak which I do not think has been noted, but which is 

 very efficient locally in its operation. 



The limestone in question is a dark-blue compact rock (pro- 

 bably the oldest stratified formation in this part of Borneo) full 

 of fissures and joints, and forming hilly tracts in Sarawak proper 

 and Samarahan. It is a not uncommon occurrence durmg 

 periods of unusual drought for the jungle clothing these hills to 

 take fire in some unascertained way, and for large tracts of the 

 vegetation to be destroyed before the conflagration dies out or 

 is e.Ktinguished by rains. Such an accident took place two years 

 ago on the Jambusan hill, and a short time previously onGunong 

 Angus (whence the present name, "Burnt Hill"), and on Mara- 

 jah, a large hill near Bidi ; and I have been informed by natives 

 that similar fires are known at the head of the Undup, where 

 I have observed from a distance extensive masses of limestone. 



When such a fire takes place, not only may we take for granted 

 that a great deal of surface-rock is more or less calcined, so as 

 to be easily removable by the heavy tropical rains ; but, there 

 being no covering of soil to speak of, and the exterior rock 

 having been merely bound together by a matted network of 

 roots and creepers, large masses of rock — long loosened by 

 weathering, or freshly detaclied by the expansion of air and 

 water in the fissures — keep falling from the higher parts of the 

 hill as their supports are burnt away ; whilst groups of burning 

 trees go crashing down the scarps, assisting the work of degra- 

 dation by collision with the inequalities in their paths. 



It is, however, subsequently to the fire that its most impor- 

 tant effects become apparent. For the next year or two fresh 

 dislodgments of rock will be continually taking place, particu- 

 larly when, after the almost daily rains, the sun shines out, 

 striking on the bared rock with rays of tropical fervour. Many 

 years elapse before sufficient soil collects in the crevices of the 

 rock to support vegetation ; and until the whitened face of the 

 hill is once more shrouded in jungle, it remains immediately ex- 

 posed to steady sub-aerial denudation ; so that, bearing in mind 

 the immense rainfall, the abundance of fissures and joints in the 

 stone, and its solubility, I am inclined to beiieve that the degra- 

 dation of these hills which goes on during the interval before 

 they again be.;ome efficiently shielded with vegetation, is com- 

 parable to centuries of waste of the same rock under ordinary 

 conditions. 



Were the limestone hills of Sarawak more gently rounded and 

 less scarped, the.r destruction through the agencies above de- 

 scribed might not be noteworthy ; but, owing to the frequency 

 of lines of old sea-clilfs and mural precipices, nearly the whole 

 of the detached rock passes at once to the bases of the hills, 

 where it is again attacked by the rains, assisted now by running 

 streams or standing water. 



Sarawak, July i A. II.\RT Everett 



An Appeal to our Provincial Scientific Societies 

 Now ihat our piovincial museums are yearly increasing in 

 number, it appears desirable to dra v the attention of the pro- 

 vincial scientific socirtics to tlieir importance as the centres for 

 the private collections illustrative o the local geulogy, natural 

 history, and archaeology which from time to time come into the 

 market. We are entirely indebted to private energy for any 

 Ikitish collections which we possess. How lamentable then is 

 it that there is no public system for centralising them in our 

 public museums, and thus savmg them fioin dispersion by thtir 

 passing into the hands of dealers or private collectors, or into the 

 possession of foreign or metropolitan museums. Every year 



witnesses such losses, which are regarded with complete indiffer- 

 ence by our local representatives of Science. It is unaccountable 

 that not one of our provincial Societies has as yet had the public 

 spirit, energy, or foresight to see the imporlanceol this work and 

 of raising a fund for the purpose of ultimately securing such col- 

 lections for the district. 



It is a question of national scientific importance. The collec- 

 tions which are formed during the present century may be said 

 to represent the "pick" of the counti-y. By-and-bj', when lo- 

 calities are worked out, and the rarity and value of specimens 

 greatly increased, we may awaken to a sense of the mistake we 

 have made in not devoting our energies less to palneontological 

 literature, and more to the formation of complete and exhaustive 

 local series and collections, and thus smoothing the path of, and 

 providing interest for, the investigators of our fossil and recent 

 flora and fauna. 



Such is the lack of originality displayed in this country, and 

 precedent is so blindly followed, that everywhere we find narrow 

 scientific cliques, so-called " Societies," apparently formed merely 

 for the sake of having social gatherings and by means of a local 

 periodical facilitating the cheap publication of the papers of such 

 as contribute. 



The energy thus expended is almost entirely thrown away. 

 Indeed, so far as the journals of these "societies" are 

 concerned, these societies are mere hindrances to the progress 

 of Science, for, did they not exist, the papers which appear 

 in their obscure journals (or " napkins," in which the "talents '' 

 of these societies lie hid) might be contributed to such as have 

 a general circulation, and thus benefit the world at large. I 

 would most earnestly impress on^our scientific Societies the great 

 importance of devoting their energies more to the formation 

 and preservation of complete and exhaustive local collections. 

 With such division of labour how much more accurate and rapid 

 would be the progress of the sciences of Geology and Biology. 



S. G. P. 



The Killing of Entomological Specimens 

 A NOTE in a recent number of Nature, reminds rae 

 of some experiments I made about 15 years ago upon the action 

 of the vapours of volatile liquids (hydrocarbons, chloroform, &c.) 

 on insects, my object being to find an expeditious and painless 

 method of killing entomological specimens. Several vapours 

 produced insensibility from which the insects recovered more or 

 less rapidly, but bisulphide of carbon vapour killed them effec- 

 tually. 



My method of applying It was to place a few layers of blotting 

 paper, lint, or cotton wool, on the bottom of a wide-mouthed 

 bottle, pill box, or other convenient place of execution ; then to 

 pour a few drops of the liquid upon this and confine the insect 

 In the receptacle, which on account of the great density of the 

 vapour need not be very accurately closed. The actiun of the 

 vapour must be continued a few minutes after signs of Ufe have 

 disappeared, or the ivisect will recover. 



The most obstinate of beetles succumb without a struggle, and 

 the most delicate of moths or butterflies are uninjured, provided 

 the liquid itself does not touch them. Butterflies may be killed 

 after they are pinned out, by simply placing a little cotton wool 

 soaked with the bisulphide in a box near to them. 



W. Mattieu Williams 



Lecture Experiments 



The result of convection in a liquid, tending to cause the 

 upper part of the mass to be constantly at a higher temperature 

 than the lower, may be well illustrated by the two loUovving 

 experiments : — • 



Two large glass beakers are placed in front of a sheet of white 

 paper, one of ihem filled wiih cold the other with boiling water. 

 A boiling-tube filled wiih Ireslily prepared st.arch solution which 

 has been coloured deep blue by gralual addition of aqueous 

 solut on of iodine, and has then been heated until ihe colnir just 

 disappears, is plunged into the benker of cold water ; the blue 

 colour, caused to return by the cooling of the solution, will ap- 

 pear first at the bottom of the tube and then gradually creep 

 upwards, showing that the lower part of the hiated liquid first 

 becomes sufficiently cooled to cause the return of the colour. In 

 order to insure the disappearance of this colour by heat, an 

 excess of iodine must i)e carefully avoided. 



In the boiling water contained in the other beaker is immersed 

 a boiling-tube filled with the blue liquid obtained by adding 



i 



