tricity. The only difficulty in this case is to prove that electricity, in a free state, must have been present in these three different places, and then to point out, by analogical reasoning, its modus operandi in producing the effects witnessed. If every one of the phenomena generally observed in the potato-blight cannot thus be satisfactorily accounted for, I admit the reasoning falls to the ground. Let me here recapitulate the facts. Within the same field, one portion of the crop, which was protected by lightning conductors, was found in excellent condition; and, in three different places, the other, which was exposed to the action of what I will call electricity accumulators, was found in a state of decay-the leaves, stalks, and tubers, of this latter portion, presenting all the diagnostic appearances of the blight. It will now be necessary to appeal to certain electrical principles to ascertain the nature of the influence which must have been exerted, first, by the conductors, and, secondly, by what I have denominated the accumulators. Assuming the existence of two electricities - which appears to be the only rational theory of electricity, because it is impossible to conceive the existence of a composing or decomposing power, without a duality of principle-when these electricities are united they form a neutral fluid, which exists in a latent state in all bodies; when they are separated, by any means, they are then said to be free; and if accumulated, so as by their mutual attraction to force their passage through non-conducting bodies, lightning or electrical light is perceptible, and a deflagrating or destroying power is exerted. But when, by any electro-motive power, whether existing in nature or formed artificially, these electricities are continuously separated, at the same time that, through conducting bodies, a channel of communication is formed between them, then, and then only, what is called an electric current is established, which exerts not only a composing but a decomposing powerone body being generally forming while another is being destroyed. Before applying these principles to the elucidation of the effects witnessed in the experiment of the late Mr. Watkins, I must observe, that electricity is generally found to exist in a free state in the atmosphere, and the earth is, and must therefore always be, in an opposite electrical state. These electrical states mutually act and re-act upon each other, and are generally maintained in equilibrium by a neutral stratum of atmosphere, which is found to exist immediately over the surface of the earth. This neutral stratum must be of the highest importance to vegetation, as it protects the latter from any undue action of electricity; nevertheless its existence is, in a great measure, dependant upon the hygrometrical state of the atmosphere in different localities. The utility of the three non-insulated conductors will now be easily comprehended; for, by their incessant action, they must have prevented, up to the limits of their altitude, any dangerous accumulation of electricity in the atmosphere, and, consequently, performed one of the functions of its neutral stratum, by protect ing the plants, within the sphere of their influence, from any effects which we may suppose atmospheric electricity capable of producing. It is by no means so easy to estimate the series of electrical actions and re-actions that must have been produced by the three insulated conductors or accumulators. These conductors being constantly under the inductive influence of the earth, must have also abstracted electricity from the atmosphere; the free electricity they therefore contained, re-acted upon that of the earth, immediately beneath them, and increased its intensity;-the altitude of the neutral stratum of atmosphere was, therefore, reduced to the distance between the lower ends of these conductors and the surface of the earth. All the plants within the sphere of their influence must also have been electric by induction; consequently, from the non-existence immediately over the plants of any protecting or neutral stratum of atmosphere, an interchange of electrical action between the earth and the atmosphere must have continuously taken place through these plants. In such a case, it is indubitable that electric currents would be established in the stalks of the plants; and the earth being negative, and the atmosphere positive, the direction of motion of these currents would be downwards, or from the atmosphere to the earth. Therefore the leaves of the plants would form the positive pole, and the stalks, at the point of contact with the earth, and the tubers, would form the negative pole of this rheo-electric arrangement. It has been proved, that an electric current, formed in a similar manner to that which I have now described, possesses a decomposing power, identical with that of an ordinary Voltaic pile. Then, if it be admitted that the destroyed plants had been placed in these electrical conditions-and, in my humble opinion, it scarcely admits of a doubt-it follows that the blight observed upon them was produced by their vital functions having been interfered with by the decomposing power of electric currents. If the premises warrant this conclusion, every one of the phenomena of the potato blight will be easily and satisfactorily accounted for. Because, the plants forming a portion of the rheo-electric arrangement, their vital fluids would, of necessity, undergo decomposition,-alkalis would be repelled to the negative pole, and oxygen to the positive. A series of polar arrangements would also exist in the different parts of which the plant is composed,-first, between the upper and the under surface of the leaves; next, between the lower end of the stalk and the fibres; and, lastly, as it has been experimentally proved with respect to various kinds of fruit, between the stem and the principal eye of the tuber. Now, to limit consideration to the decomposition of the carbonic acid which is elaborated during vegetation, the oxygen of this acid, instead of being expelled by the leaves, would be retained at their positive or upper surface, and this effect would necessitate an alkaline deposit at their negative or under surface therefore, by the retention of this excrementitious oxygen, some other acid would unquestionably be formed; but the nature of this latter acid would depend upon the organic substances either naturally existing in the plant, or abstracted from the earth by capillary action. For instance, if sulphur were present, sulphuric acid may be formed; or from the constant presence of carbon, hydrogen, and oxygen, acetic acid may be formed; or again, the retained oxygen being electric, may attract azote even from the atmosphere. In this latter case, nitric or rather nitrous acid may be found, and thus may not only the brown blotches on the upper surface of the leaves, but the greyish ones on their under surface, be satisfactorily accounted for. The same reasoning will account for the upper surfaces of the tubers, near the stem, being effected at the commencement of the disease, and not the under, and also for the great effect generally observed in that part of the stalk in contact with the electric surface of the earth. In the preceding view of the cause of the potato blight, I have assumed the electricity of the earth to be, as it generally is, negative, and that of the atmosphere positive; but it is well known that the atmosphere, on the contrary, is sometimes negative. Now, if this negative state of the atmosphere were general in any locality, there can be no doubt that the earth in that locality would be positive. Various experiments are on record which clearly prove that these latter electrical conditions of the earth and the atmosphere, even supposing the non-existence of any superinduced electric currents in the plants growing in the locality, are incompatible with a healthy state of vegetation. The reason must now be obvious; for, in this case, the leaves of the plants, instead of giving out oxygen, as in a healthy state, they always do, when the sun is above the horizon, must have a tendency to take it from the atmosphere. The oxygen abstracted from the moisture of the earth would then be retained by the tubers, and would there go to the formation of a noxious acid. The under surface or the eye of the tubers would therefore be affected, and not the stems; and the leaves, for some time at least, would afford no other indication of the decay going on, than a generally increasing paleness of appearance. Of course if, in such circumstances, electric currents were established in the plants, the decay would be much more rapid and decisive. It would be quite unnecessary, on the present occasion, to pursue these deductions any furthur; but if there be truth in the principles to which I have appealed, then I submit that I have inductively proved that the blight which partially effected the crop of the late Mr. Watkins was produced by electricity, and, consequently, as like effects may safely be attributed to like causes, the potato blight in general must be of electric origin. Though every mind may not be prepared to ratify these conclusions, let me at least hope that I have now placed this vitally important subject in such a light as to preclude the probability of its remaining without further investigation. LIST OF REGISTRATIONS EFFECTED UNDER THE ACT FOR PROTECTING NEW AND ORIGINAL DESIGNS UTILITY. FOR ARTICLES OF 1848. Nov. 30. Clarke & Timmins, of Birmingham, for a music-stool, screw, tube, and box. Dec. 1. Ephraim Slynn & William Green, of Wolverhampton, for a cabin-door lock. 4. Captain H. Mangles Denham, R. N., of the Senior United Service Club, Pall Mall, for a tiller. 5. Joseph Faulding, of 40, Robert-street, Hampstead-road, for apparatus for applying steam and vapour heat to parts of the human body. 5. James Hayes, of Elton, Huntingdonshire, for the "pedomanu-motive." 6. Thomas Barr, of 10, Park-lane, Glasgow, for a duplex block for printing yarn in the hank. 7. John Gedge, of 4, Wellington-street, Strand, London, for a safety hammer for the locks of percussion fire arms. 7. Henry Smith & Thomas Woodhouse Ashby, of Stamford, for an agricultural cart. 12. James Tod & Son, of Edinburgh, engineers, for a railway carriage cork buffer. 12. John Rogers, of 4, Doris-street, Princes-road, Kennington, for an improved draft accelerator. 13. T. H. Thompson, C. E., of the Strand, for a blindroller. 13. James Wallis Dann, of 46, Cromer-street, Gray's-innroad, London, for an improved ball-valve. 15. Mac Lardy & Lewis, of Salford, for an improved flyertop for preparing and spinning cotton and other fibrous substances. 15. Robert Sargison, of New Walsoken, Wisbeach, millwright, for an improved straw-shaking machine, for separating the corn from the pulse. 16. Timothy Adams Jordan, of 20, Pump-row, Old-streetroad, London, for a tyre for a wheel. 16. Stephen Barton, of Nelson-street, Bristol, for an open or close carriage, with a round-cornered glass front. 16. Myer Myers, of Birmingham, for a pen-holder. 19. William Henry Neuber, of 76, Long Acre, London, for f 244 444 Irish and Scotch Patents. Dec 19. Thomas Davey Durrant, of Lindfield, Sussex, for an improved sound-board receiver for pianofortes. 20. Joseph Samuel Hodge, of 462, New Oxford-street, Middlesex, for a safety pocket or receptacle. 20. John Hitchen, of Priestland Cottage, Tarporley, in the county of Chester, for a vent-peg. 23. Thomas Davis, of Warwick, for a thrashing-machine. 26. Thewlis & Griffith, of Phoenix Iron and Tool Works, Warrington, for a churdle Joo in That have passed the Great Seal of IRELAND, from the 17th November to the 17th December, 1848, inclusive. To Joseph Eugene Asaert, of Lille, in the Republic of France, machinist, for improved means of obtaining motive power.Sealed 22nd November. Pierre Frederick Gougy, of Leicester-square, in the county of Middlesex, Gent., for improvements in apparatus and machinery for raising, lifting, and otherwise moving heavy bodies.Sealed 30th November. Alfred Vincent Newton, of the Office for Patents, 66, Chancerylane, in the county of Middlesex, mechanical draughtsman, for certain improvements in the manufacture of steel, being a communication to him from a foreigner residing abroad.Sealed 2nd December. Joseph Lillie, of Manchester, in the county of Lancaster, engineer, for certain machinery or apparatus applicable for purifying and cooling liquids, and for purifying, condensing, and cooling gases.-Sealed 5th December. Hugh Bell, of London, Esq., for certain improvements in aerial machines, and machinery in connection with the buoyant power produced by gaseous matter.-Sealed 9th December. List of Patents Granted for SCOTLAND, subsequent to November 22nd, 1848. To John Armstrong, of Edinburgh, for improvements in constructing water-closets.-Sealed 23rd November. Edward Duncombe Lines, of Chelsea, soda-water manufacturer, and Samuel Luz Freemont, of Love Lane, London, for im |