216 Retrospective Criticism. 



ascending vapour. The roots of plants on trenched ground, therefore, receiving a greater share 

 of both this heat and moisture (and which their prone direction is always in quest of), accounts 

 sufficiently for their superior growth in such circumstances. That this fountain of subterra- 

 nean heat and moisture is also " the mother of dew" may be easily proven : but, as this perhaps 

 would be trenching on the confines of the constituted authorities of science, I shall desist; 

 though I believe no practical gardener, who has observed what takes place in hot-beds on trenched 

 ground, &c , would hesitate one moment in agreeing with, Sir, yours, &c. — J. M. Chelsea. 

 Sept.il. 1827. . 



Dove's Dung in Samaria. — During the famine in Samaria, a cab of dove s 

 dung sold for five pieces of silver. Josephus (Ant. Jud. 9. c.4. §4.) says this was used as a 

 substitute for salt. {Buckingham's Travels in Palestine, vol. ii. p. 396. 1822.) In the Encyclo- 

 pedia of Gardening, \ 34. you have followed the opinion of Sir J. E. Smith, that it was used for 

 the purpose of forcing some species of vegetable. — A. G. Near Barnsley. 



The Gardens of Brighton — Sir, In your Gardener's Magazine for this month, I 

 observe that during' last August you passed through this town in your route to the Continent, 

 and that you honour us with your passing observations on our state of gardening. You are, I 

 am sure, aware of the different obstacles with which we as gardeners have to contend in this 

 place ; the most prominent of which are the rapid increase of buildings which deprives us of the 

 free circulation of air, and the destructive effects of the sea breezes ; these last are so fatal to 

 almost all garden productions, that our very market is supplied principally by gardeners residing 

 from one to forty miles from the town. You will readily perceive that under these circum- 

 stances it requires some fondness for the pursuit to engage an amateur to attempt forming a 

 garden, and I admit we do not rank high as gardeners. Mankind however are generally sti- 

 mulated to exertion by encouragement ; a horticultural society established here a few years since 

 has done much for us, and I have to regret that, without meaning to detract from the merits of 

 those gardens which you accidentally saw, your attention was not called to some others which, 

 I flatter myself, would not have been entirely unworthy of your inspection. You would at least 

 have discovered a zeal in the pursuit, we should have been flattered by your commendations or 

 improved by your suggestions, and your public remarks might have been applicable to other 

 places struggling wirh similar difficulties to our own. Should chance lead you again to this 

 town, I beg to call your attention to the gardens of Mr. Gulburd, Mr. Juds, Mr.Tamplin, Mr. 

 Thunder, Mr. Mitchell, and Mr. Strange, all of whom will, I feel convinced, be happy to receive 

 your visit. — I. M. November, 1829. 



Chemical and Geological Elections of Plants — Your readers are under great 

 obligations to Mr. A. Gordon for his catalogue of American plants, with some reference to their 

 habitats given in Vol. IV. p. 463. of your Magazine. That gentleman would however have greatly 

 enhanced the benefit, had he extended a more particular observation to the chemical nature of 

 the soil in which the several genera and species grow, and favoured us with an account of the 

 results. The deficiency of information in this particular is, however, a failure in which Mr. 

 Gordon is not singular: almost every botanical writer is grievously wanting in this respect. The 

 chemical character of the soil is in almost all instances intimately connected with the texture of 

 the soil, and in that respect influences the vegetables which it bears ; but, independently of that 

 circumstance, the chemical composition of the soil exerts a more direct and more important 

 influence on the election which plants have for any given situation, than either the elevation, 

 aspect, texture of the soils, degree of moisture, temperature, or shade. Cultivators will never 

 team from books what plants are appropriate to their respective situations, until writers on 

 botany and travellers shall designate the abodes of plants by their chemical site, or by their 

 geological site, which includes and pretty accurately expresses their chemical site; instead of 

 referring, as writers of good repute now do, to the adventitious characters of banks, barren grounds, 

 barren pastures, wet sandy places, wet thickets, and the like. A calcareous sand differs as much in 

 its native produce from asilicioussand, as a limestone wood differs from a forest on argil. We have 

 not yet even a book which alludes to the geological or chemical elections of plants, and we pine 

 in ignorance till Mr. Bicheno shall please to give us a guide to that geological knowledge of our 

 native plants, of which he has given us a tantalising specimen in a communication to the 

 Linnean Society. If Mr. Gordon would carry back his recollection to the regions he has visited, 

 I doubt not, he could give us some very important particulars, of which he has left us ignorant. 

 What is the base of the alluvial sand, in which he finds five species of maple to flourish ? Is it 

 the detritus of a limestone ridge of hills, or is it siliceous ? The vegetable matter we can easily 

 assume to be common to both'; yet the compost will afford a congenial nidus to widely different 

 plants. Is his marshy s., which I conceive to be marshy sand, calcareous or siliceous? Or does 

 it mean marshy soil ? If the latter, is it purely vegetable, or mere peat or bog ? And, if not, 

 are the earthy materials aluminous, calcareous, siliceous, or what other? Are the hills all of 

 similar substance (which is most improbable) ? If not, are they of granite, mica slate, gra- 

 wacke slate, porphyry, limestone, sandstone, clay chalks, magnesia rocks, coal-measures, or of 

 what other substance ? Are they clothed with a thick coat of vegetable matter, or are the plants 

 rooted in the clefts of the rocks, and in the native earths, without much adventitious covering? 

 What is the soil which Mr. Gordon designates as var. s. ? and what are the chemical cha- 

 racters of the earthy parts of it ? Mr. Gordon's communication is so interesting and important, 

 that I hope he will view with indulgence this attempt to render his observations as extensively 

 instructive and useful as possible. — Causidicus. Jan. 18. 1829. 



The Term Humane Mousetrap. — Sir, As you applied the term humane to my 

 method of catching mice (Vol. V. p. 109.), you must bear the blame of the criticism of Mr. 

 French (Vol. V. p. 724.) ; for though my method of drowning is not so cruel as that of starving 

 to death, still I did not call it humane. I am, Sir, &c. — James Rollins. Liverpool, Jan. 7. 1830. 



The Soude, as invented by a Wrexham Mechanic. — Sir, in the last volume of the 

 Gardener's Magazine (Vol.V. p. 656.) you mention a machine called the soude, and say that "one 

 of the simplest, cheapest, and best shower baths hitherto in use may be formed from it." Allow 

 me to lay before you the following extract from a lecture delivered to the Wrexham Artisans' 

 Society by John Murray, Esq. F.L.S. F.G.S., &c, on the 30th of April, 1828, with a note appended 

 to the manuscript of the lecture by the highly respected and talented treasurer and secretary of 

 that Society. I am, Sir, &c. — Thos. Edgeivorthjun. Wrexham, Dec. 30. 1829. 



" I have to exhibit a very useful and ingenious piece of mechanism made by one of the 

 Wrexham mechanics, who is a member of this Society." (The lecturer here produced a 

 nursery shower-bath, and thence took occasion to explain the philosophical principle of its 



