88 Henry RiddeU on 



from still water a constant stream can be (obtained by which to 

 work a watervvheel. 



1 6. Robert Fludd's wheel, already mentioned, dated 1618. 



17. Another syphon, dated 1733 



18. Mercury bellows, This was apparently the last wheel 

 receiving the honour of a notice from the Royal Society, and was 

 the subject cf a discussion between the inventor, a Frenchman, 

 and Hie famous Dr. Papin. In the absence of a drawing a des- 

 cription could scarcely be followed. 



19. A mercury wheel in which the mercury was directed 

 from buckets at one side of the wheel to those upon the other, 

 and thus one side of the wheel was supposed to be kept always 

 overbalanced and continual rotation caused. There were many 

 allied inventions which need not be mentioned. 



20. A wheel described in the '■'Mechanic's Magazine^' ot 

 1827, in which exhausted cylinders wert used in the same manner 

 as the mercury buckets m No. 19. This parallels No. 9419 

 of 1842. 



21 and 22. Illustrated a curious wheel described in the 

 ^'Joitfnal of the Franklm Ifistitute" which cannot be described in 

 the absence of a drawing. 



23. A wheel described in the '■'Mechanic's Magazine'' of 

 1823, using the Rangely rotary pump to supply water to drive a 

 waterwheel. The inventor seems to have been under the idea 

 that nothing was spent in power in the rotary pump except the 

 trifling friction of the parts, and thus ass\nnes that the wheel which 

 is connected to the pump will be able to drive the latter and yet 

 have a surplus of power to devote to a useful purpose. 



24. A wheel driven by the water issuing from an archimedian 

 screvv. The inventor assumes that the water in the screw is in 

 equilibrium, and that no power is required to raise it except that 

 lost in friction. The inventor of this wheel in a public advertise- 

 ment offers to supply large or small models of the machine, or for 

 a consideration to superintend the making and setting to work of 

 such machines for any client desiring such accommodation. 



25. A double cone railway, where the inventor proposes to 



