166 



KNOWLEDGE. 



May, 1913. 



potential difference of ten thousand volts, so that 

 half an inch means fifty thousand volts. Now, the 

 twenty-four doublings represent an increase of eight 

 million times, so that the original charge may be 

 put at about one eight-millionth of this, or the one 

 hundred and sixtieth part of a volt. At the same 

 time the amperage, it must be remembered, is, even 

 in the case of the fifty thousand volts, practically 

 unappreciable, so that the high voltage obtained does 

 not mean practical efficiency, say for lighting or 

 power purposes. 



These few experimental illustrations all demon- 

 strate the mysterious principle of the origin of 

 electricity from contact. They do not, however, 

 demonstrate how or why electricity originates from 

 contact. Here we come to the boundary line 

 between the known and the unknowable as far as 

 physical science is concerned. The rest eludes our 

 senses. We come, as it were, to the horizon line of 

 the phenomenal, beyond which lies the noumenal 

 that is not attainable by the material senses. 



All that can be said is that it seems as if the law 

 of contact was in the case of electricity merely a 

 particular case of the operation phenomenally of 



some very vast law that also makes itself manifest in 

 many other ways. The mystery that peeps out in 

 contact electricity ma} - in the noumenal world be 

 one with the mystery that eludes us when we seek 

 for the cause of many potent influences arising from 

 contact in quite other departments of human 

 observation, not only in chemistry and other material 

 sciences but in purely human energies. The power 

 of " the touch of a vanished hand " may be as truly 

 due to polar sympathies as the force that arises from 

 the contact of dead zinc and copper. And in the 

 great unity of things which it is beyond us to grasp 

 the hidden cause of each may be one and the same. 

 It may be that there was no mere playful conceit, 

 but a hint of profound truth, in those pretty 

 impromptu lines with which Dr. Herbert Mayo 

 celebrated the epoch-making discovery by Faraday 

 of electro-magnetism : — 



" Around the magnet Faraday 

 Was sure that Volta's lightnings play, 



But how to draw them from the wire ? 

 He took a lesson from the heart : 

 'Tis when we meet, 'tis when we part 



Breaks forth the electric fire." 



THE HORNET AS A PET. 

 By G. HURLSTONE HARDY. 



I began to be interested in Vespa crabo, with the appearance 

 of which I was much impressed, in my early youth. It then 

 happened that I acquired a large triple observation hive, but 

 no honey bees. I had to be content with placing therein the 

 nests of several kinds of wild bees, of course, separately, and 

 studied their habits and those of their parasitic enemies. 



One summer, when I had in hand two colonies of the large 

 common bumble bee, and was hopeless of acquiring hornets, 

 I determined to add wasps. With the assistance of two 

 schoolfellows I smoked and dug out a nest of three horizontal 

 combs. These we placed in the central hive, with a few 

 young wasps and the queen wasp. These young wasps had 

 very recently emerged, and could hardly yet fly ; however, 

 they cleaned and fed the young in the combs. We fed them 

 with jam, house flies, and other insects. In about one week 

 a sufficient brood of newly-hatched working wasps were able 

 to forage abroad and rear all the brood. Unfortunately, the 

 queen disappeared, and the community did not increase to the 

 normal size of a full autumnal brood. The most curious fact 

 observed was that certain lazy wasps made a habit of awaiting 

 at the alighting boards of their bumble bee neighbours, and 

 there beg to be fed. They never threatened the bumble bees, 

 who seemed willingly to feed them without realising that they 

 were fatally neglecting their own broods. 



My wasps never entered the nests of the bumble bees, and 

 they did not resent being closely observed as long so the hive 

 was not shaken and was only approached from behind. 



Many years later I observed hornets flying very late in 

 the summer evening about trees in Chiswick, but it was 

 some time afterwards, whilst I was casually walking down 

 Chiswick Lane, that I discovered hornets busy around four 

 straw hives in the front garden of a cottage. I entered and 

 asked the proprietor to let me observe them. I found that he 

 kept these hornets for pets, and that he had no bees. We 

 had a long conversation on hornets and again on another 

 occasion, but I regret that circumstances prevented my 

 visiting the locality for several years. When I did eventually 

 go there, my acquaintance was not to be found. I hoped to 

 establish colonies like his in my own garden at Twickenham, 

 but have never been able to do so. 



I learned from my acquaintance much of great interest, and 



I was confirmed in all my somewhat conjectural ideas about 

 the habits of hornets which vary much from those of their 

 cousins, the commoner wasps. Friends are apt to accuse me 

 of joking when I aver that the hornet is a gentle, inoffensive 

 creature very suitable for a pet ; but it really is so, and the 

 reason is easily explained. Accustomed to hunt high in the 

 tree tops she remains ignorant of the savagery of the average 

 school-boy and she seldom experiences the malice of man or 

 becomes aware of the trepidation of woman at the mere sight 

 of a wasp. Her services must be overwhelmingly beneficial 

 in woods and orchards. At midsummer she forages much in 

 the night. The honey bee gathers from sunrise to sunset but 

 works hardest in the forenoon and slackens towards evening. 

 The wasp begins an hour earlier and ends an hour later. 

 Now hornets work throughout most of the twenty-four 

 hours if the weather permits. When I visited ray 

 acquaintance in Chiswick Lane he had two hives 

 occupied by numerous inhabitants and one other by 

 a very young colony ; he lifted up the latter hive and 

 let me observe the queen at work. He said he felt no 

 danger whatever, although she was at that date being assisted 

 by her first brood of workers. I greatly desired to know how 

 he managed to have inhabitants for his hives year after year, 

 inasmuch as hornet colonies were reputed to be not like those 

 of honey bees, but like those of wasps, started anew each year 

 singly in a new spot by a surviving queen after hibernation. 

 He said that every year, since he had started with a transplanted 

 colony, queens had voluntarily chosen hives in his garden. 



Having lost such a unique opportunity of learning more, I 

 regret that now I can only surmise that queen hornets either 

 hibernate in the old nest or inherit an inclination to frequent 

 the locality of their birth, habits which are both contrary to 

 those of the common wasps and bumble bees, though the 

 upholsterer bees and their nearest relatives do exhibit an 

 excessive attachment to the spot from which they emerge. 



If ever I succeed in getting a colony of hornets, I shall 

 install them near the top of my house rather than near the 

 front door steps on the ground, as did my acquaintance. I 

 have no fear whatever of these innocent and useful creatures, 

 who seem quite willing to share our dwellings with us if 

 encouraged to do so, but a high elevation would suit their 

 habit of high flight. 



