DIVING. 



Diving. 



Manner of 



diving. 



Trials of 

 tlingcrt'i 



tion consisting of six parts of wax, two of Venetian tur- 

 pentine, two of pitch, and two of hogs lard, melted to- 

 gether. To dispose of the pipes h and i, without in- 

 convenience to the diver, they are conducted through 

 buckles, at the sides of the lower half B of the cylinder, 

 and are then conducted up to the surface behind him, 

 not at his side, as shewn by the Figure ; and for this 

 reason the pipes are represented by dotted lines. The 

 pipes turn down, and have a small reservoir W applied 

 to each, so that they can be unscrewed. These are for 

 the purpose of collecting that small quantity of water 

 which will force itself through the pores of the leather 

 of the pipes, as well as by the condensation of the 

 breath, and would, without such a provision, be in con- 

 tinual motion, and render the breathing very disagree- 

 able. Four hooks are soldered to the lower part of the 

 cylinder at W, for the purpose of suspending such 

 weights as will ballast the diver, so that he can descend 

 rapidly ; or by throwing them off, the quantity of air 

 contained in the machine will render it so buoyant as 

 to rise to the surface without assistance. 



The author gives the following instructions for using 

 a machine of this kind : When the diver, after being 

 made acquainted with all the parts of the machine, has 

 put it on, and suspended from it the proper weights, 

 let him enter the water at any convenient place, and 

 advance till it reaches to his eyes, while the end of the 

 pipe is held by a person on the bank. If the diver can 

 then breathe with ease, and if no water forces itself into 

 the pipe, which must be kept by a float sufficiently 

 above the surface of the water, he may proceed till it 

 covers his head, having first taken the precaution to tie 

 it strong rope to one of his arms. After this he may 

 stop for some time, and then gradually go deeper and 

 deeper, making signals that he finds himself at ease, by 

 pulling the rope, or by speaking through the pipe. If 

 a man excretes himself in this manner, for several days 

 successively, still increasing his depth, he will soon be 

 able to dive boldly, and to move under the water with 

 ease and freedom. When he wishes to ascend, it is 

 necessary only to unhook the weights, which will drop 

 to the bottom, and being then lighter than an equal vo- 

 lume of water, he will rise to the surface. To preserve 

 the weight from being lost, a particular rope must be let 

 down to the diver, upon his making certain signals, and 

 which he may fasten to the weight before he unhooks 

 it. 



By following these directions, a resolute man may be 

 taught in the course of a few days to dive to a mode- 

 rate depth ; though, on account of various preparations 

 and unforeseen difficulties, the author employed five 

 whole weeks in teaching one who was unacquainted 

 with swimming. This man, called Frederic William 

 .Toachim, a huntsman by profession, dived in the 

 above apparatus into the Oder near Breslau, where the 

 water was of considerable depth, and the current strong, 

 on the 24th of June 1 797, before a great number of 

 spectators, and sawed through the trunk of a tree 

 which was lying at the bottom. He shewed also, that 

 he could have fastened sunk bodies to a rope in order 

 IM be drawn up, and that, in case any impediments 

 lionld prevent the use of the saw, such trunks might 

 be hewn to pieces by an axe. It clearly appears, there- 

 fore, that two men furnished with such apparatus, 

 would saw to pieces large beams of wood lying at the 

 bottom of rivers, which are often a great obstruction, 

 and, on account of their size, cannot be otherwise remo- 

 M(|. 



It unnecessary for us, after having described M. 



Klingert's machine, to enter into a detailed description Diving. 

 of any other of the same class, such as Kessler's water ""V^ 

 armour, which he proposed in 1617, and many others, 

 as the one which we have described seems to contain all 

 that isgood in the others. Some of them have an essential 

 difference in the apparatus for breathing, viz. by forcing Another 

 down the air by bellows or a pump, and thus conden- ' no( ' e , ? f 

 sing it into the machine, until its elastic pressure is suf- 

 ficient to repel the pressure of the water. The foul air 

 which has been breathed, may, in this case, be suffered 

 to escape from the machine through a valve into the 

 water, or it may be conducted to the surface by a pipe. 

 Of this kind is the apparatus contrived by Mr Tonkin, by Mr Toa- 

 and employed for some time in raising parts of the kin. 

 wreck of the Abergavenny East India ship, which was 

 unfortunately lost off Weymouth in 1 80i. It consisted 

 of a body of copper with iron boots, put together and 

 jointed in the manner of coats of mail ; the whole is 

 then covered with leather, and afterwards with canvass, 

 painted white to distinguish it under water. The arms 

 are made of strong water proof leather ; and the place 

 for sight is about 8 inches diameter, glazed over with a 

 plate of glass an inch thick. The diver is sunk in this 

 machine by means of weights, fastened equatorially 

 round the waist of it ; and he is suspended by a rope, 

 by means of which his situation is changed at pleasure. 

 A flexible air tube communicates with an air vessel in 

 the boat above. Through this tube the diver gives his 

 instructions, and obtains his supply of fresh air. This 

 machine was used with very good effect in a depth of 

 near 7 fathoms water, and enabled the diver to direct 

 the operation of several curious machines, such as saws 

 for clearing away the ship's decks, and making suffi- 

 cient openings to give him access.to the treasure below, 

 as well as tongs, &c. for taking up the heavy goods by 

 tackle in the vessel above. 



The next class of diving machines which we shall rjiy 

 describe, are those in which the diver is shut up, with eels. 

 a sufficient quantity of air to supply him a considerable 

 time ; and in this he descends, proper contrivances be- 

 ing provided, to enable him to work nt the bottom, 

 where he can only continue as long as his .supply of air 

 is sufficiently pure for respiration, which will be but a 

 short time, unless the machine is enormously large ; for 

 a man will, according to an experiment of Dr Halley's, 

 consume a gallon of air in the course of a minute, and 

 as he throws out the impure air to mix with the rest, 

 it will so contaminate it, that by the time he has 

 breathed one half the air, the whole will become very 

 unfit for respiration, and oblige him to be drawn up to 

 recruit it. We understand, that in a vessel containing 

 a ton, a single man may remain an hour without in- 

 jury. 



The diving bladder contrived by Borelli, is the ear- BoreDi's 

 liest of this kind. It is described in his Opera Post- diving 

 Ituma, to consist of a vessel of copper, which he calls bladder. 

 vesica, or bladder, and is about two feet diameter. 

 This id to contain the diver's head, and is to be fix- 

 ed to a gout skin habit, exactly fitting to the shape of 

 his body. The person carries an air pump by his side, 

 by means of which he may condense or rarify the air in 

 the vessel, and thus make himself heavier or lighter on 

 the same principle as fishes do, by contracting or di- 

 lating their air bladder. Within this vesica there are 

 pipes, by means of which a circulation of air is contri- 

 ved; and, by this arrangement, Borelli supposed the ob- 

 jections to which all other diving machines were liable 

 woidd be obviated, particularly thatoftheair; "themois- 

 ture by which it is clogged in respiration, and by which 



