1842.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



333 



Payerne's invention, little need be said. Tliey were, with one ex- 

 ception, decided failures; and even in tlie experiment which was 

 most successful, the whole achievement consisted in bringing up a 

 small piece of the wreck of the Royal George, to prove the divers 

 had actually reached the bottom. This was the mighty result of the 

 new discovery which, as announced, was to enable man to dwell with 

 ease at the bottom of the ocean, and to inhale water for air! 



Let us examine the means by which this feat was accomplished, to 

 gee whether, trifling as it was, any part of it can be reasonably as- 

 signed to the operations of Dr. Payerne's box and materials. We are 

 not informed of the size of the bell employed by General Pasley, but 

 from the circumstance of its being constructed of wrought iron, and 

 made expressly to carry on the operations against the wreck of the 

 Royal George, we must conclude that it was at least of the size of 

 those formerly employed by Dr. Halley and Mr. Smeaton, which con- 

 tained GO cubic feet of air. The cylinders of compressed air, we 

 have already stated, would furnish a further supply of 160 cubic feet 

 of the pressure of the atmosphere. The two divers would, therefore, 

 have a supply of air equal to 220 cubic feet. With this supply they 

 might have remained under water, if consuming but one gallon per 

 minute, for ten hours; but estimating the quantity of air requisite to 

 sustain life without much inconvenience, from actual experiment at 

 the Polytechnic Institution, we will take it at two hours and a half. 



How long they did remain below each time, the reporter fails to 

 state, but it would appear that the bell was drawn up nearly as 

 soon as it reached the bottom ; therefore, we may presume the 

 longest experiment did not last more than half an hour. Conse- 

 quently there could not have been occasion for the Doctor to have 

 generated more air than the supply he took down ; and however 

 simple and easy the manipulation of the apparatus may be, he might 

 have saved himself the trouble of turning the handle of the box. 

 Another question arises, if the Doctor did generate any gas what 

 became of it ? It is known that the volume of air expired from the 

 lungs is very nearly equal to the quantity inspired, and we find that 

 even with the whole supply of air from the cylinders, the water was 

 still six inches within the bell. This could not have been, had any 

 quantity of gas been generated, for it must have expelled all the water 

 and forced itself out of the bell. 



The naivete uith which the authorised reporter records the suc- 

 cess of the last experiment at Spithead, is extremely amusing. Lieu- 

 tenant Hutchinson and Dr. Payerne's assistant descended with an air- 

 pipe supplied by a small air-pump, and with this they appear to have 

 been more successful than was Dr. Payerne with his cylinders of com- 

 pressed air, and his mysterious box. This mode of descending in the 

 diving hell, which is called in the report "an experiment of still greater 

 interest" than any previously attempted, it will be at once perceived 

 is the plan first adopted by Smeaton, and since generally adopted ; 

 the only variation being that the pipe was smaller, and was taken 

 down in the bell instead of being inserted in the top. It thus ap- 

 pears to be admitted, that so far as the experiments extended, the old 

 plan is more advantageous and much less troublesome than the new 

 invention, which was so extravagantly puflTed. 



As Dr. Payerne does not disclose the process by which he professes 

 to be able to decompose water in sufficient quantities to supply 

 oxygen gas for respiration, it would be useless to speculate on the 

 practicability, if any snch plan were applied to works under water, 

 So far as his experiments have gone, they have, we conceive, proved 

 nothing. The Doctor exhibits u mysterious box ; he professes to 

 have in it two simple and cheap materials, which are sufficient to 

 generate air sufficient to support life for an indefinite time ; he tries 

 its powers, and the effects produced are no greater than if the box 

 and materials had no existence. Were we to speculate respecting 

 the contents of such a box we might imagine it to contain highly 

 compressed oxygen gas. Fifteen cubic feet of gas might be com- 

 pressed into a case the size of a portable writing desk ; and as one 

 cubic foot of oxygen would support life nearly five times as long as 

 atmospheric air, he wou'.d thus carry under his arm a supply equal 

 to 75 cubic feet of common air. This speculation, however, can 



scarcely be correct, or the Doctor's mysterious box would have been 

 more efficacious than it proved. 



Though Dr. Payerne's experiments have, we consider, entirely 

 failed to show that he possesses any peculiar art of transmuting water 

 into air, they have been productive of advantages by proving that 

 operations under water may be conducted with a much smaller supply 

 of air than has hitherto been considered necessary. 



The great publicity which Dr. Payerne has succeeded in giving 

 to his claims to be the discoverer of an important scientific principle, 

 challenges examination, and has induced us to bestow this notice on 

 his experiments. It would be presumptuous to assert that the Doctor 

 has made no such discovery, but if he have, he has been most unfor- 

 tunate in his mode of announcing it to the world ; for whilst claiming 

 to be a philosopher, he assumes the garb of a charlatan. 



FIRE-PROOF BUILDINGS. 



Sir — The constant danger and frequent loss to merchants, solicitors, 

 and others, through the destruction by fire of the papers and docu- 

 ments entrusted to their care, has induced my clients to erect an ex- 

 tensive range of " fire-proof" chambers and offices in the Old Jewry, 

 City. At this time some description of the method adopted, viz. of 

 omitting timber, and of using cast iron girders and brick arches to 

 carry the floors, whereby each room becomes in a manner an arched 

 vault, may not be unacceptable to your readers, although the idea is 

 not new, the more especially as many professional men, engaged, as 

 they stated, on somewhat similar works, have inspected the buildings 

 and sketched the details, for the purpose of obtaining information 

 respecting the construction. 



Fis:. 1. Elevation of iron Girder. 



Fig. 2 Looking upwards. 



r>» C5^ 



Fig 3. Section of Girder and Arches. 



c I, cenlre line. 



The walls are built without any bond plates, instead of which, in 

 the height of each story, according to the height of it, 5 or 6 courses 

 of wrought iron hooping liXJ in. is laid in the walls; it must be laid 

 quite flat, and well lapped together or bound round a brick at the 

 joinings and passings. The hooping was tarred and sanded for better 

 adhesion to the mortar, and kept in about an inch from the face of the 

 wall, as the rust would otherwise stain the plastering. 



The girders were of various lengths, from 11 ft. up to 18 ft. Gin. 

 clear bearing; they rested 9 in. at each end on 4 in. York templates, 

 and were placed 7 ft. apart from centre to centre. The girders ex- 



3 A 



