80 Queries and Answers. 



turnip beetle. The remainder of the reviewer's objections are included in 

 these words. " Turnip-seed, committed to properly prepared ground, makes 

 its appearance on the fourth day. Now, suppose that the eggs of the insects 

 are attached to the seed, as is represented by Rusticus, is it probable that they 

 can be transformed first into grubs, next into chrysalides, and lastly into 

 perfect beetles, in the short space of five, or six, or even fourteen days ? This 

 is for Rusticus to explain ; and it is to be hoped that his description only is 

 erroneous, not his doctrine." The same writer offers some strictures on 

 Rusticus's act of steeping in brine the seeds of turnip ; but these, as he has 

 misunderstood Rusticus, we need not notice. We have accurately given, in 

 IX. 632., the experience of Rusticus, in his own words, on this point. — J.D. 



Art. VI. Queries and Answers. 



WHAT are the Heat and Moisture best adapted for the Production of the various 

 Fruits ? — Since too much dryness is certainly injurious, and too much moist- 

 ure is generally believed to be so, what is the best medium of moisture for the 

 flowering of the various descriptions of fruit trees ? The horticulturist can, 

 in a great measure, command temperature ; and he knows, in regard to it, 

 what to aim at : but moisture has been less attended to, at least as regards its 

 quantity in measurable terms. The indications of the hygrometer ought to 

 be attended to with as much care as those of the thermometer. Ought there 

 not to be a series of experiments commenced, in order to determine the quan- 

 tity of both heat and moisture best adapted for the production of the various 

 fruits? — R. Turnham Green, Nov. 5. 1833. 



Plants, the Leaves of which will strike root. — I should like to see, in your 

 Magazine, a list of those plants the leaves of which will strike root, and form 

 plants ; such as Bryophyllum calycinum, Kalanchoe crenata, Gloxinia, A'\oe, 

 &c. — T. Rutger. Shortgrove, December, 1833. 



An Essay on variegated Plants, pointing out how Variegations are produced, 

 and their Uses, if any, in ornamental Scenery, with Lists of the most beautiful 

 variegated Trees, Shrubs, and Plants, is desired by Mr. Rutger, and also by 

 T. G. and J. W. 



Self-acting Gate. — Might not a machine be contrived by which any interior 

 gate of the approach (where it is necessary to have interior gates) could be 

 opened on the passage of a carriage wheel over a certain part of it fixed on 

 the road ; the weight being made to act on some concealed portion of the 

 machinery, by which the gate would be opened, and remain open sufficiently 

 long for a carriage, &c, to pass, and then shut of itself? — T. A. B. Easthwaite 

 Lodge, Lancashire, Dec. 24. 1833. 



Parker's sympathetic gate (fig. 8.) is of this description. On the approach 

 of a carriage, the gate opens, apparently by its own volition, and closes again, 

 after the carriage has passed through, without any apparent cause. The effect 

 is produced by small plates let into the ground at short distances from the 

 gate, which, when the carriage wheels roll over them, descend like a weighing 

 machine, and act upon certain levers concealed in a trunk under the ground. 

 By means of these levers, a toothed wheel is made to revolve, and to turn a 

 toothed pinion affixed to the swinging post or axle of the gate, and thus to 

 throw it open, or to close it. (Encyclopaedia of Agriculture, 2d edit., § 3107.) 



In the Encyclopaedia of Cottage, Farm, and Villa Architecture will be found 

 figured and described (§ 831.) a most valuable description of gate, for the 

 lodges to the approach roads of country residences, which we would most 

 earnestly recommend to the attention of master gardeners, land stewards, and 

 country architects and builders. This gate ( fig. 9.) is the invention of 

 Mr. Saul of Lancaster, and the object of it is to enable the gate-keeper to 

 open the gate in the night time, from his bed-room, without the trouble of 

 dressing, or going down stairs. So benevolent a design ought to be seconded 

 by every gardener. In fig. 9. g represents a horizontal shaft placed in a tunnel 



