APPARATUS FOR RAISING WATER SIR,-As your valuable Magazine appears to be open to experimentalists, as well as to practical men, I trust you will find the following communication worthy your notice. I found, by repeated experiments, that after filling a (wine) bottle with boiling water, and then turning it bottom up, the air that passed into the bottle as the water ran off, became rarefied to double its bulk or volume; for immersing the bottle neck downwards in cold water, it became half full of water in a short time. I then pursued the experiment in the manner described in the prefixed draw ing, and found the result similar to that in the bottle. Description of the Drawing. AA, a tin boiler, about twelve inches deep, closed at the top, containing two or three gallons of water kept boiling by the fire in pan BB. CC, a tin pipe, one inch and a half bore, soldered into the top of AA, and passing down about seven inches into the boiling water. At the bottom of CC are several small tubes, intended to make the passing air spread through the boiling water. DD, a nine-gallon beer cask, having two strong additional heads, and the upper original head perforated with holes to let the condensing water spread like a shower bath; the whole cask made air-tight by pasting paper twice over it. E, a small funnel, with a water-tight plug on the top of DD. F, an inverted syphon, kept full of water, which covers a water-tight plug or valve. G, a pair of bellows, with a valve opening upwards; connected below is a copper pipe, one inch and a half bore, passing into the lower part of DD.There is an air-tight cock added to this pipe at Q, and another on the pipe HH (connected with the tin boiler, AA), which passes into the upper part of DD. The copper tube, II, conveyed the raised water into DD, near the top, in order to complete the condensation; I then began by letting a little water in from the funnel, E, above, still keeping its plug under water. Then followed the Operation, The boiler, AA, being close, and having no communication with the atmosphere but through its pipe, CC, I first opened my air-tight cock, QQ, then made a few strokes with the bellows, G. The moment hot air came out of its valve, I stopped the air-tight cocks, then let in a little water from the funnel, E, and the water rushed up instantly through the tube, II, and filled the nine-gallon cask about onehalf. To let the water off, I opened the cock in the pipe H, and it all ran off through F. I made soine strokes full. I have given you very rapidly after the pipe, II, became the experiment as I made it, but it now appears to me that the bellows had better blow into CC; then both the air-tight cocks might be removed, and a much simpler mode substituted in lieu of them, gabriq I am, Sir, Your obedient servant, I SIR H. DAVY'S METHOD OF PROtecting the copper of shIPS. 275 through a rag into another bottle; + Bradford, July 18th, 1825. ▾ ilf 9/42.30 FACTS PROVING THE EFFICACY OF gle adhesion of any kind, and, as far as could be judged from the smoothness and appearance of the copper, it had not been at all worn by any chemical corrosion. The iron, which was about an inch and half. in thickness, is considered a sufficient protector for two voyages more. 2. The Elizabeth yacht, belonging to the Earl of Darnley, was protected by two pieces of malleable iron in the stern, in May last, equal to about 1-125th of the surface of the copper. After being employed in sailing during the summer, she was examined in November, when her bottom was found free from adhesions of any kind, and apparently untouched. The copper was bright, and even the nails not tarnished. In the course of the summer a few small barnacles had adhered to the rust of iron, which were easily and immediately washed off; but no weed or shell-fish had ever fixed on the copper, which appeared in the same state as when she left the dock. The following examples we owe to the kindness of Dr. Traill: The ship Huskisson, belonging to Mr. Horsfall, was lately in dock, after a voyage to and from Demerara, where she lay some weeks, in a river remarkably favourable to the adhesion of parasitical animals and weeds; yet, when I examined this (From the Annals of Philosophy.) vessel, her copper appeared perfectly 1. The Carnebrea Castle, an In- clean, as far as it could be seen, when diaman, belonging to Messrs. Wi- she was purposely set by the stern gram, of 650 tons burden, was pro- in unloading, in order to show ber teeted last spring by a quantity of copper at the bows as low as possiiron in four portions, two on the ble. The Captain stated, that bebow, and two on the stern, equal to fore coming into port, while yet in from 1100th to 1-110th part. She clear water, he had seen her bottom has since made the voyage to India, and was for some time in the Ganges. She appeared bright and clean during the whole of the voyage out and home; some mud collected on her bottom in the Ganges, but immediately disappeared when she be gan to sail. She was put into a dry dock about a fortnight ago, and her bottom examined by Sir H. Davy, the proprietors, and various other persons. Every part of her bottom was bright and clean, without a sin even to the keel, and it seemed to. him quite clean, This ship was defended by two bars of malleable irom bolted along the sides of her keel by copper fastenings, which covereda about 1-90th of the surface of herr copper. The Elizabeth, a vessel defended exactly in the same manner, with metals in the same proportions, had made the same voyage. Both had been newly coppered when they last left Liverpool; and the Elizabeth's 276 SIR H. DAVY'S METHOD OF PROTECTING THE Copper of ships. copper appeared equally clean as that of the Huskisson when unloaded; but as she did not enter a graving dock, we cannot absolutely say whether she was quite clean, especially as the copper of the Dorothy (about to be mentioned) appeared equally so, until she was seen in the graving dock, when the flat part of her bottom was found to be quite covered with barnacles. The copper of the Huskisson, there is reason to believe, was perfectly clean, as was proved in the next case. The ship Dee-A very large vessel belonging to my relative, Mr. Sandbach. The ship was newly coppered about twelve months ago, and a bar of malleable iron, about 7-8ths of an inch thick, and three inches broad, was fastened on each side of the keel by iron spikes. It covered about 1-90th of the surface of her copper. Since that period she has made two voyages to Demerara, and was, at the conclusion of the last, put into a graving dock, when her copper was found perfectly free from corrosion, and there were scarcely any substances adhering to it, except a very few minute barnacles, near the keel fore and aft. This ease shows, that over defence was not the cause of the foulness of the bottom of the Tickler, for both in this vessel and in the Huskisson the proportion of iron to the copper was greater than in that ship. The iron spikes employed to fasten the iron on the keel of the Dee, were so much corroded, as to endanger the falling off of the bars; copper nails are, therefore, to be preferred. The Dorothy.-Dr Traill states, that the following particulars of the Dorothy's outfit and return, were communicated to him by his intelligent friend Mr. Horsfall, one of the owners of the ship, in the beginning of May : "The Dorothy had been coppered about a year, and had made one voyage to Bombay and back to this port, when, in May, 1824, it was determined to place bars of iron, four inches broad, and one inch thick, along her keel, covering about 1-70th part of the copper, in the expectation that the iron would at least so far preserve the copper from corrosion, that it might be permitted to run a second voyage to India without being renewed, which can seldom be done with perfect safety. The iron extended from one end of the keel to the other, and was fastened on with copper nails with large heads. The Dorothy, thus defended, sailed again for Bombay in June, and returned to Liverpool about a month since. She was put into the graving dock yesterday (May 3), and an examination of her bottom took place as soon as the water had left her. "The copper appeared no more reduced than at the termination of the first voyage. The iron was diminished generally about three-quarters of an inch in breadth, and from one quarter to half an inch in thickness. At the ends of the vessel, for about two or three feet, the iron was much more reduced than at any other part! It was covered with the usual rust, not at all resembling cast iron, under similar circumstances. The flat of the ship's bottom, from end to end, and from six to eight feet in breadth, was full of fleshy barnacles (lepas anatifera) of uncommon length, and a few of the large hard shell species (balanus tintinnabulum).*” that the specimens of the lepus anatiNote by Dr. Traill. We remarked starboard than on the larboard side fera were considerably larger on the of the ship. On noticing this to the larboard had been the lee side of the Captain, he informed us that the vessel, almost constantly during the passage to Europe, and consequently most deeply immersed in the watera circumstance in the economy of these animals not unworthy of notice. i B point, a, the beginning of the impulsive force, let the bob, B, be then drawn back to y, directly over P, a mark to which the oscillatory bob is drawn every time of movement till the wedge is driven under the n end of the board as far as the point b on the wedge. NOTE. Size of the wedge one inch and three quarters square at its base, d; and length, ce, three inches and a half; width, one inch; weight of bob, one pound and three quarters; distance from h to p, 18 inches; weight of board, with weight on it, 10 pounds; length of string, 4 feet. The bob being let go, it took 73 strokes to drive the wedge three inches; point b coinciding with n, for the first experiment. EXPERIMENT SECOND. |