a Public Institution. 741 



disrepute by what has been pompously announced to 

 the public as improvements of them ! And hence we 

 may see of what infinite importance it would be to the 

 progress of real improvements, to have some general 

 collection of useful mechanical contrivances, constructed 

 on the most approved principles, and kept constantly in 

 actual use, to which application could be made as to a 

 standard^ in order to determine whether experiments 

 which fail are owing to errors in principle, or to blun- 

 ders of the workmen employed in the construction, or 

 to those of the servants employed in the management 

 of the machinery. 



And how very useful would such a repository be 

 for furnishing models, and for giving instruction to 

 artificers who may be employed in imitating them ! 

 Workmen must see the thing they are to imitate; 

 bare descriptions of it will not answer to give them 

 such precise ideas of what is to be done as to prevent 

 their being liable to mistakes in the execution of their 

 work. 



But this is also the case with mankind In general, 

 and even with the best-informed ; for how great must 

 that effort of the imagination be that is necessary to 

 form any adequate idea of what we have not seen ! 

 Descriptions, though they be illustrated by the best 

 drawings, can give but very imperfect ideas of things ; 

 and the impressions they leave behind them are faint 

 and transitory, and seldom excite that degree of ardour 

 that ought to accompany the pursuit of interesting im- 

 provements. 



Few indeed have an imagination so extremely vivid 

 and susceptible as to become enamoured of a descrip- 

 tion or of a picture. Something visible and tangible 



