The latter lefs probable.

The oxidation contradicts the hypothefis of two electric

bodies.

Variation of Dr.

Ash's experi

ment.

When a long
copper wire was

connected at the
end with zinc
(under weak
fulph. acid)
hidrogen was

earlier given out

They tell us of two kinds of electricity coming from the gal vanic apparatus one from the zinc end, the other from the copper end: the former being positive, the latter negative.

Two diftinct fluids moving in contrary directions could not poffibly exift in the galvanic trough; by reafon of that fluid proceeding from the zinc meeting that coming from the copper in each of the cells, and confequently establishing a constant equilibrium, without producing any effect. When the decompofition of water is only taking place in one veffel (admitting the above objection to be of no weight) the phenomena admit of an easy explanation by this hypothefis; but when two veffels are used connected by a wire arch, it cannot in any fhape be adequate; for as we have in each veffel both oxigen and hidrogen gafes, there must also be both pofitive and negative electricity; these two contrary fluids would of course have to meet each other in the connecting arch, and according to another part of this theory form sensible heat *.

The pofitive wire, if a base metal is always oxidated; this effect is known to be facilitated by the electrical agency. According to the principles in question, it would be retarded by the power of affinity existing between water and positive electricity. When the wires of a galvanic apparatus are brought into a metallic folution, no hidrogen is given out at the nega tive wire, but the metallic oxide is reduced. Now if metallic oxides be compofed of water and the metal, the negative electricity would combine with the water, and hidrogen gas would be evolved-the very reverse of the fact.

My reason for being thus particular in the examination of the hypothefis of Mr. Richter and Dr. Gibbs, is to prepare the mind of the reader for fome experiments which I think will contribute to the firmness of the hypothefis, which fuppofes water to be a compound, and that the hydrogen is carried from the pofitive to the negative wire by the electricity.

The well-known experiment of Dr. Afh (with the plate of zinc and fiilver in a dilute fulphuric acid) I had occafion to vary in the following manner. I took a copper wire about eighteen inches long, and bent it in the middle so as to form

*They are of opinion that these two fluids combined form caloric. They alfo hold with Dr. Priestly that what are now termed metallic oxides are the respective metals combined with water.

two

parts of the
(bended) wire:

two parallel legs, about two inches diftant from each other, at the nearer This I laid in an earthen difh filled with dilute muriatic acid. I then brought a piece of zinc in contact with one of the ends: bubbles of hidrogen were immediately given out by that part of the copper. After bubbles had appeared for about two inches down this leg, I observed bubbles on the end of the other leg, they now proceeded down the two legs till at laft they appeared on the part where the wire was bended. I afterwards laid a piece of zinc at one end of the fame dish and a piece of gold at the other. I prepared a metallic arch with two pieces of wire, one of gold, the other zinc, foldered together. The zinc end I connected with the piece of zinc in-and fo likethe dish, and the gold end with the gold. After the contact had been made about ten feconds, bubbles appeared on the between gold piece of gold. The distance was about twelve inches. I now placed the pieces of gold and zinc at half the diftance, and made the communication with the fame arch. The bubbles now appeared upon the gold in about half the before-mentioned time. Upon bringing the pieces ftill nearer together, the gold gave out gas almoft inftantly, but yet in all the three inftances I had time to obferve that the bubbles always appeared first on that fide the gold next the zinc.

wife in a compound condu&or

and zinc.

inferred that the

neg. ftate; but

municated

I think from the above experiments that the difengagement Whence it is of hidrogen from the gold does not depend upon its negative difengagement of ftate, for this quality must have been produced on the gold in hidrogen does every one of the three inftances in the fame time, from the not depend on a communication being always made by an arch of the fame that the elec length. On the contrary, it proves that the electricity difen- tricity is com gaged from the zinc is communicated to the gold through the through the inintervening liquid. If we obferve the length of time taken up terpofed liquid. in its paffage through this medium, we hall fee that it does not agree with the laws of electricity. Is it not therefore proba ble that when the oxigen of the water combines with the metal, the hidrogen combines with the electricity of the metal, and a compound of this kind obferves thofe laws confiftent with the phenomena.

In each of the cells of the galvanic trough a quantity of this Probability that the hidrogen is compound is diffused through the liquid.. The moment a com- in combination munication is made between the two ends, the electricity en- with electricity. ters each of the copper-plates, leaving the hidrogen in bubbles

on

1

on the furface. As this electrated hidrogen (if I may be allowed the expreffion) does not move through the liquid with the facility of the electricity itself, the necessity of a surface of copper equal to that of the zinc is obvious. It is plain that only a proportionate quantity will be carried through the whole Objection to the feries. This fact I have afcertained in attempting to render apparatus dethe apparatus propofed by Mr. Wilkinfon and yourself useful Vol. VIII. p. 3. for all experiments. The shock is even less when the surface of copper is lefs than a fquare inch.

fcribed in our

on the couronne

of Voita.

How the elec

the hidrogen in the exterior

cells.

4

The quantity of electrated hidrogen in each cell increases tricity increafes from the copper end to that of the zinc in an arithmetical pro greffion. The electricity only exifts in its fimple form while it is paffing from the copper furface through the two metals to the zinc furface. It there combines with another portion of hidrogen, which it leaves at the next copper furface, and fo on accumulating in quantity the longer the feries it has to pass through. In the decompofition of water by the galvanic trough the vessels in which this is performed may be confidered as one cell in the feries. The electricity feizing the hidrogen at the pofitive wire and giving it out at the negative,

Mechanical operations of the bees.

XI.

Memoir on the Origin of Wax †.

By FRANCOIS HUBER,

Member of the Society of Natural Philofophy and Natural,
Hiftory of Geneva.

IT has been thought strange that the word wax fhould seldom

occur in a book which treats of bees alone: but nevertheless as in the courfe of my obfervations, I had not attended to the products of their induftry, I could only have repeated what had been faid by Swammardam and Reaumur, and that did not feem to me to be neceffary.

I knew that these infects collected abundantly upon the anthere of flowers, that they are acquainted with the method of

*This fact is very obvious when the copper furface is very clean. The hidrogen under contrary circumftances is employed to reduce the oxide.

+ From Journal de Phyfique, &c. Pluviofe, An. XII.

opening

opening them, of gathering their duft, keeping it in the cavities of their hind legs, and carrying it to their hives.

flowers:

It had been obferved that the particles of this duft fwells in Examination of water, and that, when one of them bursts, an oily liquor runs the pollen of out, which floats on its furface, but did not mix with it; from these experiments, repeated on the dust of a great number of flowers, it was concluded that they contain the principles of wax, but it was admitted that these must undergo a peculiar elaboration in the body of the bee, fince, according to the experiments of Reaumur, a flexible wax could not be made from the duft of the antheræ.

*

It will be seen from several paffages in my work that I had The true origin adopted this opinion: a fingle obfervation of Burnens changed of wax remained fo long all my ideas. The true origin of wax might have been sooner unknown from known, had there been any suspicion that it was not already an opinion that difcovered. shall now ftate how I was led to doubt, and what

I have done to verify my new conjectures.

it was difcovereds

the enquiry.

I was in Switzerland in 1793; the farmer of the estate on Observations which I refided had many bees, and the greater part of his which led to hives having been flocked in former years, the combs with which they were filled reached to the ftands, confequently there was no room to conftruct new ones. We remarked, however, that the working bees carried in a confiderable quantity of this fecundating powder.

There was alfo in the fame apiary fome fwarms of that year, the hives having only been stocked a day or two; in fome of them the combs were only began, in others they were larger, but in all of them there were vacancies to fill up, and much work to do. We obferved with aftonishment that the bees of these fwarms did not carry in the pollen, and that, nevertheless, they worked with activity in the construction of new combs, and in lengthening thofe already commenced. Where, therefore, did they procure materials for their edifices? After these observations, we suspected that it was not from the duft of the ftamina, and that they had a very different use for it than that for which it was believed to be intended. We however found that it was not impoffible to explain these extraordinary facts, without abandoning the hypothefis of Reau

*The name of M. Huber's fecretary; which deferves to be known to the cultivators of natural history.

mur,

Exp. I.
Is pollen necef-
fary to the pro-

mur, by fuppofing that the bees of the old hives stored up fo much pollen in their combs for their future wants, while those of the new swarms did not carry it outwardly on their legs, in the infancy of their establishment, because they had no cells in which they could depofit it: it might be fufficient to enable them to construct their combs, if they were at liberty to fly to the flowers, procure their pollen, and return to their hives after having filled their stomachs, where it must be elaborated and converted into perfect wax. It was to obviate these doubts that I undertook the following experiments.

FIRST EXPERIMENT.

On Bees in Confinement with Honey alone for their Nourishment. Muft bees eat pollen to be in a state to produce wax? This was the first question which I thought it necessary to investigate; duction of wax? the method of trying the experiment was obvious; it was only required to keep the bees within their hives, and thus prevent them from collecting or eating the fecundating powder.

Wax from honey alone.

On the 24th of May, Burnens lodged a swarm in a straw hive, with as much honey and water as was necessary for their confumption, and he closed the doors so that the bees could not get out and the air be at the fame time renewed.

At first the bees were very uneasy, but became calm on removing the hive to a cool dark place: their captivity lafted five days; they were permitted to come out in a room, the windows of which were fhut: we then examined the hive more conveniently. We first noticed that there was no honey left in the veffel which had been filled with it, with the fole intention of feeding the confined bees; and were more aftonished to find five combs of the most beautiful wax, fufpended from the roof of the hive; they were perfectly white, and very brittle. This refult was very remarkable; however, before forming a conclufion from it, that the honey with which these bees were fed had enabled them to produce the wax, it was necessary to enquire whether it could not alfo be explained in another manner.

The bees which I had employed had doubtless collected the duft while they were at liberty.

They might have done fo the evening before, or on the very day of their confinement, and might have enough in their stomachs, and in the cavities of their legs, to extract from it all the wax which we had found in their hive.

But