M.ipU Strgar.'-^ChemUal affJ Mechamcol InvefiiUfi, JOj 



tlons grounded on exifting fads, it is afcertained fhat America is now capable of pro^ 

 ducing a furplus of one eighth more than its own corifumption i that is, on the whole, 

 about 135,000,000 pounds, which in the country may be valued at 15 pounds weight for 

 6ne dollar. Dr. Rufli mentions many other benefits his country may derive from this in» 

 valuable tree, and concludes his paper with an account of fome of the advantages of fugar 

 to mankind ; not merely, as commonly confidered to be a luxury, but as an excellent 

 wholefome and nourifliing article of food. Annexed alfo is an extrafl from the report of 

 the committee of the Britifli privy council on the fubjedl of the African flave trade> 

 Containing Mr. Botham's ftatement of the mode of cultivating a fugar plantation at 

 Batavia*. 



VI. 



T'/je Progre/i of Mechanical Di/covery, exemplified in an Account of a Machine for cutting 



Files. iW.M.\) 



X HE folly and confequcnt diftrefs of purfuiiig experiments In chemiflry, for the fok 

 {jurpofe of commercial advantage, has been repeatedly obferved both by public Writers and 

 in private life. The obfcurity which attends the procefles of this art, the imperfe£lion« 

 of theory, and the feduftions of hope, have united to lead men in purfuit of medicines of 

 uncommon powers, and agents which fliould convert the cheaper ftietals into gold and' 

 filver. It is a fubje£]t of no wonder, to thofe who have not fufFered their mental 

 habits to be vitiated by thefe fedudive analogies, that difficulties and difappointment 

 fliould attend the life of a man thus employed. But mechanics have, in general, been 

 more favourably regarded. A number of fimple and admirably ufeful efFeds are produced 

 by the operation of machines. We daily fee improvements produced by means eafily 

 underftood. The mechanic who endeavours to ftrikc into a new path, finds he can 

 reafon from what has been done before him, and ufually begins his work with a convic- 

 tion that the refults he is dcfirous of obtaining will infallibly happen. Hence it is that 

 a prodigious number of new fchemes find their way into books; on which both the author 

 and the reader fet a high value, and of which the futi'Uy is difcerned only by a few prac- 

 tical men. Some of my readers have fuppofed this fource of information to be much 

 more produftlve than it really is. A very flight enquiry concerning new machines and 

 ,inventioi?8, whether they have been carried into efFed, and whether they have fuperfeded 

 the old methods of operation, will immediately ftrike out of the lifl; of valuable articles 

 not lefs than nine tenths of the objeds to which the public attention is folicited. And 

 if it be aflerted that the defcription of fuch abortive projeds might be of ufe to afford 

 hints to fpeculators, I muft take the liberty to obferve, that it is a mofl ferious thing to 

 engage in a new invention, and a no lefs ferious duty in the editor of a public work to 



* To avoid the impHtation of plagiarifm, I muft take notice tliat the two laft paragraphs appeared in an 

 anonymous publication in the year 1794, but were written by myfclf. N. 



f As the obfervation on the wrapper, thai all fafers tvitboni r.ame or fi^nature are'tvritten by the Editor, has 

 been overlooked by fome readers, who have made enquiry refpefling the authors bf fuch papers, he ha* thought 

 it expedient in future to add his initials. ' 



Vol. II.— Oct. 1798. Sf ^ j«r 



