them. Store-houses are constructing on the most improved principles; and the whole work is to be fire-proof. But much remains yet to be done; the town of Sheerness, or Blue Town, as it is called, must be removed, and the north or sea wall widened, and raised; the foundation is already impaired, and much greater damage may be sustained, when the coffer-dam which defends it shall be taken away. The great dock is not large enough for the Howe, and will require alteration. Some doubts have arisen as to the expediency of laying out so much money on a foundation of sand; the ground on which the whole fabric stands was originally made by old ships and lumber heaped together, and some curious specimens of ancient naval architecture have been and are daily brought to light.

When we promised in a former volume, to offer some remarks on the rise and progress of the "dry rot," we were not aware that the subject had been so ably treated by Mr. John Knowles, of the Navy Office. That gentleman, in a work published in 1821,* has given a full description of this dreaded epidemic in our ships; the volume is luminous, and deserves the attention of every person connected with naval or mercantile affairs. Mr. Knowles has not confined his researches to the cause, effect, and remedy of this disaster, but has given a general history of woods most adapted

*An Inquiry into the means which have been taken to preserve the British Navy, 4to.

for ship-building, together with a series of philosophical experiments which have been tried with various success, on the best means of promoting the durability of ship-timber; and when it is considered how many lives of our valuable seamen, and not our's only, but of other nations, may owe their preservation to his detail of those discoveries, we shall not hesitate to bestow on him the highest title which can be given to man," a benefactor of the human race."

The term " dry rot," as applied to defects in the ships of the navy, says Mr. Knowles, "is a late introduction, and of no earlier date than 1808; hence an opinion has prevailed, that it is a disease of recent occurrence, and not what is the fact, that it has existed in all times, and that the name alone is new," p. 109. To prove that it is coeval with the days of Moses, he cites the 14th chapter of Leviticus, in which it is accurately described under the name of "leprosy in houses," and the same remedies directed to be applied, which have been practised with success in our own time. With respect to ships, its prevalence in the latter part of the seventeenth century, is fully proved from the writings of Mr. Pepys, who gathered toad-stools in their holds "as big as his fists." Hence it may fairly be concluded, that from the first invention of ships, they have been more or less subject to this decay, according to the state of the wood at the time of its being cut; to its application in naval

architecture; and to the degree of attention paid to the ventilation and cleanliness of the ships; to the climates in which they have been exposed, and the service which they may have performed.

In a work, professing for its object the history of our navy, it would be inexcusable to pass over a phenomenon which tends to the rapid decomposition of its chief material; and we conceive the surest mode of prevention, is to point out to mariners its causes, and to teach them how to detect it in its incipient state. For these purposes the work of Mr. Knowles is strongly recommended.

Considerable alarm was justly excited in the country, by the decay of our ships in the most active and urgent period of the late war. The term

dry rot," Mr. Knowles observes, is only applied to the decomposition of timber, when accompanied with fungus; air, heat, and moisture, which pormote vegetation, are necessary to its production; great care should therefore be taken in the application of stoves to remove damp, otherwise the effect may be produced which is sought to be avoided. Wood constantly wet or dry, is not subject to this decay, while the parts of a ship exposed to heat and moisture or partial immersion, soon begin to shew signs of decomposition. From these few remarks it is obvious, how much the preservation of a ship depends on the attention of officers; in narrowly inspecting every part, removing casks,

Such

or goods which have remained long in one position, dry scrubbing, sweeping, and ventilating as low down as it is possible to penetrate, beneath the orlop deck. Infinite, have been the improvements in our navy, since officers have applied themselves to considerations of such vital importance. The true picture of a ship of war of the old school, is to be found in Roderic Random. it continued to be in 1782, and was not much improved in 1792. The store-rooms were a chaotic mass of most things requisite for a ship, although nothing was to be found when wanted. The first instance we can remember of their being arranged in that beautiful order, now so generally observed in the service, was on board the Boston, in 1795, when commanded by the present Vice-admiral John Erskine Douglas. This was done by the carpenters of the ship, under the direction of the captain; the advantages soon became so apparent, that many captains followed the good example; and at length, government receiving into its councils some of the most active and influential officers of the navy, adopted the mode of fitting store-rooms throughout the service; and great are the benefits derived from it. The wings or intervals between the ship's sides on the orlop deck, and the various articles stowed there, such as cables, rope, planks, &c. are kept perfectly clear and clean, so that a person may, or ought to pass completely round the ship, below her line of fluitation. This space, intended principally for the carpenters in time of

action to drive their shot plugs, was formerly the receptacle of every species of lumber; births for messing, midshipmen's and quarter-masters' hammocks, chests, bags, and lanthorns; in short, it was a hot-bed, not only for dry rot, but for disease. The pump-well was sometimes so neglected, that as late as 1808, three men fell dead in the well of a ship of the line in the West Indies. Ventilation and the use of fires, have entirely eradicated this evil, and it can never occur again, but from want of attention in the captain. The method of fitting the bulk-heads of the well and store-rooms with lattices, is productive of two advantages, the circulation of air, and the prevention of fire: the yeomen having been known to conceal themselves there, to drink and smoke, and lights having been left locked up in them. From the first of these causes, the St. George was burnt at sea, in the year 1759; and from the second, the Ajax was said to have suffered in the Dardanelles, in 1806. A close smell or confined air on board a ship, in harbour or at sea, in fine weather, is generally a sign of neglect and bad management.*

"The carbonic acid gas, formed from the breath of the crews and decomposition of timber, being heavier than atmospheric air, descends by its gravity into the hold, and is absorbed by the water in the pump-well; which at a temperature of 44° has the power of holding its own bulk of carbonic acid gas, and this power is increased by an increased temperature." (Knowles.) This is what we call bilge-water. The iron mast (should it be found to answer) will effectually cure this evil, The heat of the sun acting on it, will so rarefy the air within as to ensure a constant ventilation in the pump-well.