What is called 'a French sulphurator,' whose great merit appears to be 'simplicity and cheapness,' was also exhibited. It is described as 'a tin box for holding the sulphur, placed on the upper side of the pipe of a pair of common bellows. The sulphur gets into the pipe through small holes made for the purpose in the bottom of the box, and, in order that no stoppage may take place, a small hammer-head attached at the end of a slight steel-spring, is fixed on the under side of the bellows, a gentle tap from which, now and then, keeps up a continuous fall of sulphur into the pipe.' It is said, that 'these appliances, which may be attached to a pair of bellows for little more than sixpence, answer every purpose for which they are intended, equally as well as a more expensive machine.'

At the same time with this contrivance, some bunches of black Prince Grapes were shewn to the assembled horticulturists, which could only be preserved from mildew by frequent applications of sulphur. The bunches are to be afterwards cleaned by dipping in water, or what is considered preferable, 'syringing on all sides with a fine syringe,' which process, it is well to remember, disturbs the bloom on the fruit least when directed 'downwards, or obliquely, as rain would fall.'

As the season for gardening operations is coming on, Mr Rivers' account may be mentioned of his mode of growing strawberries in pots; it will be found to involve certain combinations opposed to ordinary practice. 'About the second week in July,' he says, he filled a number of six-inch pots 'with a compost of two-thirds loam, and one-third rotten dung, as follows: three stout pieces of broken pots were placed in the bottom, and a full handful of the compost put in; a stout wooden pestle was then used with all the force of a man's arm to pound it, then another handful and a pounding, and another, till the pot was brimful, and the compressed mould as hard as a barn-floor. The pots were then taken to the strawberry-bed, and a runner placed in the centre of each, with a small stone to keep it steady. They were watered in dry weather, and have had no other care or culture. For two or three years, I have had the very finest crops from plants after this method, and those under notice promise well. If the pots are lifted, it will be apparent that a large quantity of food is in a small space. I may add, that from some recent experiments with compressed earth to potted fruit-trees, I have a high opinion of its effect, and I fully believe that we have yet much to learn on the subject.'

There is a committee sitting at the Admiralty, to devise a method for the uniform lighting of ships and steamers at night, the object being to diminish the chances of accident or error to vessels at sea. And apropos of this, Mr Babbage has published a plan which will effectually prevent one lighthouse being mistaken for another: it is, that every lighthouse, wherever situated, shall have a number—the numbers not to run consecutively—and no two adjoining lights to have the same numeral digits in the same place of figures. There would then be no need for revolving or flashing lights, as the only thing to be done would be to make each lighthouse repeat its own number all night long, or whenever it was illuminated. This is to be 'accomplished by enclosing the upper part of the glass cylinders of the argand burner by a thin tube of tin or brass, which, when made to descend slowly before the flame, and then allowed suddenly to start back, will cause an occultation and reappearance of the light.' The number of occultations denotes the number of the lighthouse. For instance, suppose the Eddystone to be 243, the two is denoted by two hidings of the light in quick succession; a short pause, and four hidings; another short pause, and three hidings, followed by a longer pause; after which the same process is repeated. It would not be easy to make a mistake, for the numbers of the lighthouses nearest to the Eddystone would be very different; and supposing that the boy sent aloft to watch for the light were to report 253 instead of 243, without waiting to correct his view, the captain, by turning to his book, would perhaps find that No. 253 was in the Straits of Sunda, or some equally remote situation, and would easily recognise the error. When we take into account the number of vessels lost by mistaking one lighthouse for another, the value of this proposal becomes apparent. Mr Babbage shews, that bell-strokes might be employed to announce the number of a beacon in foggy weather; and he believes that the time is not far distant when buoys will also be indicated by a light. Now that lighthouse dues are to be reduced one-half, we may hope to see improvement in more ways than one.

This is but a small part of what promises more and more to become a great question—that of navigation. It is felt that, in these go-ahead days, we must be paying not less attention to our maritime than to our inland arm of commerce; and this has brought the question of wood versus iron ships again into prominent notice. The advocates of iron shew that the dry-rot, so destructive to wood, cannot enter metal; that lightness and speed, those prime essentials, are insured by the use of iron; that iron ships are safer, more easily repaired, and cheaper than vessels built of wood; and that they are more lasting. The chief objection hitherto has been the liability of iron to become foul in tropical climates; but this now appears to be in a measure overcome. According to Mr Lindsay: 'An admixture has been applied, termed "Anti-Sargassian Paint," which has been found to answer the purpose better than any yet discovered. From the experience of its properties, we cannot say that in itself it is yet sufficient; but it appears a fair substitute till some other preparation is discovered. A gentleman at Glasgow,' he adds, 'has already discovered a compound, which, being mixed in a fluid state with the iron, is expected to answer the desired purpose. There is another disadvantage which will soon be overcome—the greater liability to error in the compasses of iron ships; an error which, however, also occurs, though perhaps to a less extent, in every wooden ship. By a most ingenious invention, which will shortly be made public, such errors in any ships, under any circumstances, can at all times be at once detected.'

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