1^ Miscellaneous Intelligence. 



porous subsoil appears to us as a circumstance of the first-rate 

 importance, for where it consists of clay, our crops have invari- 

 ably been inferior to those which have grown on such parts as 

 were situated upon the sand, although assisted with more manure ; 

 and this too, when, owing to frost, no injury could be attribut- 

 able to the treading of the sheep, when feeding off the turnips. 

 So strong, indeed, is our conviction of the ill effects of an imper- 

 vious subsoil, that we have no hesitation in saying, that however 

 good the soil, or however dry it may appear, if it be situated 

 immediately above clay, no profit can be extracted from it by the 

 growth of poppies, so frequent will be the partial (or total) failure 

 of the crop." — Trans. Soc. Arts, xlii. 9. 



13. Letter to the Editor of the Quarterly Journal of Science 

 Literature, and the Arts, concerning Mr. Job Rider's rotatory 

 Steani'Engine. By Andrew Ure, M.D., F.R.S., ^-c. 



Dear Sir, — In your 16th volume, there are two letters descrip- 

 tive of the structure and performance of the above engine. The 

 first letter is signed Job Rider, the second William Boyd. These 

 letters were transmitted to me from Belfast, in order that I might 

 send you an account of the engine, for insertion in your Journal. 

 I accordingly forwarded the letters, after making two or three 

 merely verbal corrections, which certainly did not, in the slightest 

 degree, alter the sense. For the truth of this assertion, you yourself 

 can vouch, in regard to Mr. Boyd's letter, since it was from his own 

 holograph, that pages 269 and 270 of the above volume of the 

 Journal were printed*. 



It now appears that Mr. Boyd did not intend that his letter 

 should be published ; but as he gave me no hint whatever to this 

 effect, I did not feel myself justified, as a mere organ of trans- 

 mission, in withholding that letter which alone furnished an ac- 

 count of the performance of the engine. Towards the conclusion 

 of this letter, there is an observation which has given offence to 

 Messrs. Gird wood and Co., eminent engineers in this city. The 

 engine which this company made on Mr. Rider's plan for the 

 Highland Lad steam-packet, was some time ago taken out of the 

 boat, (in which it gave no satisfaction,) and has been since 

 mounted in their manufactory. Here I have seen it in action. It 

 was working the powerful blast bellows of their foundry, turning 

 a loam-mill, and impelling the turning lathes, as well as the bor- 

 ing-machinery of two extensive floors of their workshop. I have 

 therefore little doubt, both from this evidence, and the well-esta- 

 blished reputation of Messrs. Girdwood and Co., that the rotatory 



* The types were set up from Mr. Boyd's original letter, on which no alter- 

 ation had been made in the least affecting the sense.— En. 



