88 



THE GARDENER'S MONTHLY 



[March, 



will tell you the conclusion that I came to re- 

 specting this blight. I said to myself — here is a 

 bad job — these potatoes were too late planting. 

 The slight frost last night and the hot sun to-day 

 has fixed them — must plant so early after this 

 that they will be ripe before the first chance of 

 frost. Which conclusions I have carried out, 

 and believe that that was the first and last potato 

 blight that I ever saw upon the farm. While 

 your scientific readers may prefer the microscope, 

 I would advise your practical ones to keep an 

 eye open upon Old Prob. 



[1846 was the date fixed by our correspondent 

 himself for the first appearance of the " frosts '' 

 so injurious to the potato. It is not uncommon 

 to have frosts in September sufficient to destroy 

 potato plants. These cases have no doubt ex- 

 isted for many years, — but the potato disease, as we 

 all now understand it, was not observed till 1845 

 on the British Isles, though we believe a year or 

 80 earlier on the Continent. — Ed. G. M.J 



EDITORIAL NOTES. 



Spoktaneous Combustion.— The matter of the 

 origin and prevention of fires, is a question of 

 particular interest to horticulturists. The follow- 

 ing, which we find in the Journal of Chemistry, is 

 to the point : — 



" This seems a queer notion, but it is made 

 quite plausible by a recent English writer, who 

 says : " When oxide of iron is placed in contact 

 with timber, excluded from the atmosphere, and 

 aided by a slightly increased temperature, the 

 oxide parts with its oxygen, is converted into 

 very finely divided particles of metallic iron, 

 having such an affinity for oxygen that, when 

 afterwards exposed to the action of the atmos- 

 phere from any cause, oxygen is absorbed so 

 rapidly that these particles become suddenly red- 

 hot, and, if in sufficient quantity, will produce a 

 temperature far beyond the ignitible point of dry 

 timber. Wherever iron pipes are employed for 

 the circulation of any heated medium (whether 

 hot water, hot air, or steam), and wherever these 

 pipes are allowed to become rusty, and are also in 

 close contact with timber, it is only necessary to 

 suppose that under these circumstances the 

 finely-divided particles of metallic iron become 

 exposed to the action of the atmosphere (and 

 this may occur from the mere expansion or con- 

 traction of the pipes), in order to account for 



many of the fires which periodically taka plac« 

 at the commencement of the winter season." 



PiCEA Parsonsiana. — ^The history of this va- 

 riety, as recently given by Mr. Parsons in ovir 

 pages, has stirred up some of our English friends, 

 and several letters have appeared. Though Mr. 

 Parsons himself tells us that it is only a plant 

 selected from a lot of others, and that it can b« 

 kept distinct only in that way, — that is to say, 

 it is but a valuable variety. The discussion 

 turns on what species it really is. It is hard to 

 understand what rule our English friends have 

 for distinguishing species from varieties. 



In this case the distinction is of much conse- 

 quence ; for as a good garden variety it has the 

 name. Parsonsiana has the right of priority, 

 and Mr. Gordon is not justified in naming it in 

 his book P. Lowiana. If it be a good species, the 

 rules of Botany require that the botanical descrip- 

 tion as well as the name should be published, in 

 order to entitle the name to stand. Even though 

 the plant had not been described, and Mr. Gordon 

 were the first to describe it, common courtesy 

 would dictate that a name common in nurseries, 

 used in the Gardeners' Monthly, and in such a 

 prominent publication as Barron's Catalogue, 

 should have the preference over an entirely new 

 one, — especially when that name — Mr. Low's — 

 only comes in as the receiver of the plant from 

 Messrs. Parsons. It may be right in the abstract, 

 and botanists would have to fiill in, — but with 

 their own opinion of the fairness of the author 

 taking such a course. 



Those botanists, however, who are familiar with 

 the variable character of conifers, and especially 

 of Picea grandis, know well that this is but a 

 variety of that species, and Mr. Parsons' name 

 should and probably will be the name finally 

 adopted to designate it. 



Botanic Garden of Harvard University. — 

 Very few know how widely useful this celebrated 

 garden has become. In the hope that our read- 

 ers may aid or profit by it to a still further ex- 

 tent, we give the notice of Prof. Sargent's recent 

 report of its doings and condition the paat 

 year. 



IMPROVEMENTS. 



The preparatory work, having in view the pro- 

 per re-arrangement of the hardy plants in the 

 Garden, has been continued during the year. 

 The perm.anent labelling of all plants, as soon a« 

 determined, has been pushed forward as rapidly 

 as possible, and is now, with the exception of the 



