i7« 



NATURE 



[April 6, 191 1 



this that he directed my attention to an allied circum- 

 stance which interested mc much. 



He informed me that the greatest trouble which he had 

 was with rats, the jorest rats he called them. 'Ihey spend 

 the winter in the garden, and, while causing} a gtKxl deal 

 of general damage, they evince a remarkable select iveness 

 in their taste for fruit. It app-ars that they have a great 

 preference for the lemon and the mandarin, which are 

 abundant in the garden. A number of the trees carried 

 zinc guards on their trunks to prevent the ascent of the 

 rats ; but in a terraced garden on a steep slope there are 

 many which cannot be protected in this way, because a 

 rat easily jumps from a higher terrace on to the upper 

 branches of a tree growing on the terrace below. By 

 this means they had boarded and plundered quite a number 

 of trees. They touched only the lemon and the mandarin 

 trees, disregarding the common orange. But what seemed 

 to be most remarkable was the different way in which 

 they treated the fruits of these two trees. Of the lemon 

 they eat the rind, removing it completely, and leaving the 

 peeled fruit, clean and without a blemish, still attached 

 to the branch which carried it. On one tree there were 

 eight or ten such freshly peeled lemons still in their places 

 on the tree, and they presented, among the others, a very 

 curious aspect of nakedness. Having boarded a mandarin 

 tree, the rat treats the fruit in the opposite way ; he eats 

 the inside and leaves the empty skins hanging on the 

 tree. On one tree that I saw, nearly the whole of the 

 fruit had been treated in this way. Something similar 

 may be witnessed with us on gooseberry bushes in a 

 summer when wasps are abundant. The reason for the 

 different treatment of the two fruits is probably not to 

 be sought further than in the fact that the inside of the 

 mandarin is sweet and that of the lemon sour. 



So long as there are niand.irins and lemons, the common 

 orange remains untouched, but when there are no more of 

 these two thr>y eat the common orange. By the time 

 these are finished the fields and woods outside are 

 beginning to furnish food, and the rats leave the garden, 

 not to return until the winter begins again. 



In answer to my inquiry, the gardener said the rats 

 never attempt to enter the villa ; they are forest rats. I 

 asked him if they were a special kind ; he said they were 

 brown rats ; and I asked him if they were different from 

 the rats he had seen in England, and he said no. 



The daintiness of the rat, shown not only in the choice 

 of his fruit, but also in the part of it which he will eat. 

 is not the only feature of rat life which is illuminated 

 by the experience of the gardener of the Villa " Charles 

 Gamier." The annual migration back and forward from 

 the open and natural surroundings of the field and forest. 

 where in summer food is being naturally produced in 

 abundance, to the restricted environment of the highly 

 cultivated garden, where in winter food is produced only 

 by artificial devices, becomes more remarkable the longer 

 It is contemplated. The whole area of semi-tropical 

 garden on the Riviera is an insignificant quantity com- 

 pared with that of the open ground, so that the propor- 

 tion of the rat population which is able to enjoy the 

 winter villegiatttra must be very small, and must be chosen 

 or evolved by a rigorous System of selection, which prob- 

 ably rests on the fundamental principle, the right of 

 might. 



In a fertile country like that of Liguria the rats, which 

 are obliged to remain fore le mart, are no doubt able to 

 pick up a subsistence during the winter, but they cannot 

 afford to be so dainty as those that are able or privileged 

 to occupy the gardens. In any case, I suppose, it may be 

 taken to be true that a hungry rat will not hesitate to 

 «at a healthy brother rat if he can wavlav him or over- 

 come him in combat. It is not improbable that this is 

 the natural winter food of manv tribes of rats which 

 mhabit countries where food has its seasons of plentv and 

 scarcity. The shortage thus produced in the winter is 

 quickly made up by the splendid fruitfulness of the mother 

 rats when the food season returns, and the population, 

 over the year, need show no diminution; indeed, there is 

 nothing to prevent it showing an increase. In nature 

 there are accumulators of all kinds. 



We have seen, on the evidence of the fruit trees of the 

 garden, that the rats occupving it must live in that state 

 •of luxury in which the sensation of real hunger is not 

 NO. 2162, VOL. 86] 



felt. Mow do they keep such a garden of Eden to them- 

 selves ? 



That the common oranges remain an a reserve to the 

 end of the season shows that overcrowding is effectively 

 prevented. We have seen that the lemon and the man- 

 darin are preferred by the rats actually occupying the 

 garden, and apparently indifferently, because the two fruits 

 arc consumed pari passu. As it is contrary to the animal 

 nature for the strong to give way to the weak, we may 

 fe<'l certain that there is no relative aversion to cither the 

 lemon or the mandarin as there is to the common orange, 

 or one of them would be consumed before the other. 



All these facts go to show that the occupying force must 

 be a very well-organised body, and must be directed by 

 that degree of intelligence which teaches it, not only to 

 drive and keep out strangers, but also rigorously to keep 

 down its own numbers to the point at which it can, on the 

 basis of experience, expect to pass the winter without 

 being reduced to the necessity of eating common oranges. 



Bordighera, March 20. 



J. Y. Buchanan. 



The Fox and the Goose. 



The interesting story concerning a fox and its fleas 

 related by Prof. McKenny Hughes recalls one told me 

 many years ago by an old gamekeeper on Lord llchester's 

 estate at Redlynch, in Somerset. The park at Redlynch 

 is enclosed with a rough wall about 5 feet high ; the 

 keeper's cottage is in the line of this wall. 



He saw one day, whilst sitting in one of his rooms, a 

 fox coming towards the wall carrying a goose, which it 

 had slung over its shoulders and was holding by the neck. 

 Upon reaching the wall it tried to jump or clamber upon 

 it, but failed. It repeated the attempt two or three times, 

 going back a little distance and readjusting its burden 

 each time before doing so. Finding that it could not get 

 over in this way, it stood on its hind legs with its front 

 feet against the wall, and, holding the goose by the neck 

 close to the head, pushed the bill into a crack between 

 the stones. The goose fell down, the crack being appar- 

 ently too wide. A second attempt was successful, and the 

 bird dangled from the wall suspended by the bill at almost 

 4 feet from the ground. The fox then leapt upon the 

 wall, and leaning over withdrew the bill from the chink, 

 hoisted up the bird, and disappeared with it on the other 

 side. 



E. W. SWANTON. 



Sir Jonathan Hutchinson's Educational Museum, 

 Haslemere, March 28. 



The Rusting of Iron. 



I.N an article in N.ature of March 2 on the rusting ot[ 

 iron, an objection was raised to the work of Lambert and" 

 Thomson (Trans. Chem. Soc., 1910) on the ground that j 

 their experiments were carried out in fused quartz vessels. 

 The writer of the article puts forward the view that fused 

 quartz dissolves in water to produce silicic acid ; that the 

 acid produced is sufficient to dissolve the iron ; that enough 

 iron will be dissolved by the process in the course of a 

 few hours to produce, in the presence of pure oxygen, a 

 visible quantity of ferric oxide ! He cannot have supposed 

 that the probability which he discusses was not considered 

 by the authors. The object of the work was to bring 

 together iron, oxygen, and water, all of the highest obtain- 

 able purity, and to let them react in vessels which would 

 be least likely to affect the reaction. 



It was only after most careful experiments on the 

 suitability of quartz vessels that they were finally chosen. 

 A long series of experiments, lasting over several months, 

 was carried out, in which (i) fused quartz vessels, care- 

 fully cleaned, as described in the paper, (2) fused quartz 

 vessels lined with purified paratfin wax, (3) Jena glass 

 vessels lined with purified paraffin wax, were used under 

 exactly the same conditions. 



The experiments were carried out as described in the 

 paper. The apparatus was evacuated down to o-oooi 

 millimetre (as measured by a McLeod gauge) ; water was 

 distilled in from a solution of pure baryta, the conditions 

 being such that the water which came in contact with the 



