PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 395 



It is capable of copying any pattern in which the curves flow 

 into each other, and the surfaces can be touched by straight lines 

 at right angles to the length. The guiding apparatus can be in 

 a short time adjusted ; and, when adjusted, an indefinite number 

 of pieces can be made exactly alike. 



It is therefore Avell adapted for sawing ship timber, which 

 requires the shapes to be much varied ; and also for architectural 

 and cabinet Avork, in which many pieces are required to be alike. 



It may also be used to saw straight work, and for this use is 

 in some points better than common machines ; and a shop pro- 

 vided with this would, to the extent of its capacity, be relieved 

 from the expense and incumbrance of a common machine for 

 straight work. 



There have been numerous wood shaping machines, highly efS- 

 cient, and ingenious, which have produced forms similar to those 

 of this sawing machine ; but they waste timber, by cutting it 

 into chips, and also waste power. The saw wastes only the tim- 

 ber from the saw kerf, and the power necessary to reduce that 

 amount of timber to saw-dust ; and in many kinds of work this 

 will be found a great advantage. 



Ju7ie 20, 1860. M. HASKELL, 



J. K. FISHER, 

 JOHN JOHNSON", 



Coinmiftee. 



Mr. Fisher exhibited specimens of the work sawed by the model 

 machine, -some of the specimens being not only serpentine in 

 form, but with the two portions of the reflex curve bevelled in 

 opposite directions. He said that there seemed to be no ten- 

 dency in the saw to follow the grain of the wood, but that it fol- 

 lowed the prescribed path accurately. There was verj^ little 

 waste, either of wood, or of power in its use. It works rapidly 

 and is strictly automatic; so that when once adjusted to any 

 particular form, ten thousand pieces may be sawed of that exact 

 shape. He saw no reason to suppose that there would be any 

 more difiiculty in the construction or operation of a full-sized 

 machine for sawing ship-timber, than in the model. 



The report was adopted. 



GUN-BOATS. 



Mr. Fisher said that at the present time the government is 

 authorizing the construction of gun-boats which are not to be 



