October 13, 1S03. 



JOTJENAL OF HOETICULTUEE AND COTTAGE GAEDENEE. 



WEEKLY CALE(\fDAR- 



OCTOBER 13—19, 1S63. 



Sweet Sultan flowers, 

 Fieldf'ire arrives. 

 Vh-flil born, 15 B.C. 

 Vallifner (lied, 1730. Bot. 

 Foxhunting begir.s. 



20 SrSDAY AFTER TRIK. ST. LuKE 



Vngmian Crteijer leaves fall. 



Rain in 



la&t 

 36 Tears. 



Davs. 

 18 

 17 

 17 

 li; 

 15 

 17 

 17 



Son 

 P.iees. 



m. h. 

 2-2 af 6 



23 6 



25 6 



27 6 



29 C 



30 C 

 32 6 



Sun 

 Sets. 



ni. h. 



n af5 



9 5 



7 6 



5 5 



3 5 



5 



58 4 



Moon 

 liiaes. 



m. h. 



13 7 



22 8 



40 9 



46 10 



53 11 



Moon 

 Sets. 



m. h. 



S 5 



Moon's 

 Age. 



Clock 

 after 

 Sun. 



3 

 4 

 5 

 6 



5 



13 a 37 



13 51 



14 5 

 14 17 

 14 ^0 

 14 42 

 14 53 



Day of 

 Year. 



286 

 287 

 288 

 289 

 290 

 291 

 292 



From observations taken near London during tbe last thirtT-sis years, the average day temperature of the -week is 58. 9^ and its night 

 temperature 41.0°. Ihe greatest beat was 70', on the 14th, 1S45 ; and tbe lowest cold, '22°, on the 19th, 1843. The greatest fall of rain 

 was 1.04 inch. 



INSECTS AND THE ATMOSPHEEE OF 

 HOTHOUSES. 



'^_ N tkis country, at least, 

 all danger to proper- 

 ty from beasts of prey 

 lias long ago ceased 

 to exist ; but it still 

 remains a fact that 

 the condition and in- 

 dustry of the human 

 race are seriously interfered 

 with and injured by the deadly 

 onslaught of insects of various 

 kinds, with which the art and 

 ingenuity of man have not yet 

 been able to cope. In some parts of the world the in- 

 roads of certain insects are regarded with terror ; and 

 the result of their collective force, with their minute and 

 complicated machinery of destruction, baffles all the re- 

 sources of man. A correspondent writing from France 

 says that whole forests have been stripped of their green 

 leaves — left as bare as winter by the ravages of the May 

 bug. Humboldt tells us of a small ant which offers 

 invincible opposition' to the civilisation of certain parts 

 of the world hy devouring everything in the shape of 

 books and parchment, so that many provinces in Spanish 

 America cannot produce a written document a hundred 

 years old, and the results of the genius and wisdom 

 of the country cannot be transmitted to posterity. In 

 other tropical countries, we are informed that a small 

 white ant clears away whole villages as effectually as 

 would a fire or a ilood. In some parts of South Carolina 

 the Pine trees have been destroyed to an alarming ex- 

 tent by the ravages of a small white bug, which at one 

 time cleared awaj' every tree over many thousands of 

 acres. It is scarcely credible that the larvre of an insect 

 should in one season have completely destroyed many 

 thousands of acres of trees which measured 3 feet in 

 diameter and more than 100 feet in height. Then there 

 is the corn weevU, which devours storehouses full of 

 grain, by extracting the flour and leaving nothing but 

 the husks. The ravages of the locust are too well known 

 to need being explained, and are a wonderful example of 

 the formidable and dreaded power of the insect race. 

 But to come nearer home, the turnip fly and wireworm 

 are sources of great annoyance and loss to our farmers. 

 Our very ships are not safe from the ever-busy depre- 

 dations of insects ; and the embankments and docks of 

 many parts of Europe have been threatened by the col- 

 lective power of beings, the individual insignificance of 

 which might be worthy in one sense of man's contempt. 



But what, it may be asked, has all this to do with 

 the operations which most concern the readers of this 

 Journal ? It may simply be answered that no gardener 

 need be told how great a relation the insect tribe bears 

 in the battle he has yearly to fight in the cultivation 

 of many things, and more particularly in the case of 

 those plants and fruits which have to be produced and 

 No. 133— Vol. V., New Series. 



brought to perfection in an atmosphere artificially en- 

 closed and heated. The little knowledge of the best 

 modes by which insects may be impeded in their destruc- 

 tion of much that concerns us, and that is valuable to 

 us on account of the labour and means which the growth 

 necessitates, is, I think, often very forcibly brought be- 

 fore us, particularly in the case of the great host of ama- 

 teurs which are every day stepping into the ranks of 

 gardening. It has been remarked that the more arti.- 

 ficial the circumstances are under which plants and fruits 

 are cultivated, the more trouble arises from insects. 

 "While certain insects make their appearance out-doors 

 more or less every year, and give much trouble and work 

 much mischief, still it is in o^ir forcing-houses that the 

 incessant watch must be kept, and that the arm must be 

 alwaj's pirepared either for or to prevent war with some 

 determined confederacy of insects. 



The object of these notes is not so much to deal with) 

 the various compounds which are used as insect-eradi- 

 cators, nor to notice their efi"ectiveness to the end for 

 which thej' have been recommended, as to call attention 

 to a point which, it must be admitted, has not come in 

 for that share of attention from gardeners that it deserves 

 — namely, the application of some of the facts which 

 Chemistry has revealed to the composition of the atmo- 

 sphere of hothouses, and to ammonia as a preventive in 

 the case of that inveterate army of redcoats named red 

 spider, which costs us so much care and labour, and after 

 all works so much mischief. That the temperature and 

 moisture of the atmosphere of hothouses are matters of 

 great importance is beyond a doubt. All gardeners who 

 have to force flowers or fruit cannot neglect these two 

 matters with impunity. In order to apply the two 

 agents just named in the most exact degree Science has 

 furnished us with instruments for our guidance. We 

 have the thermometer to indicate the p^roper degree of 

 heat, and the hygrometer to tell us to what extent the- 

 air is charged with moisture. And this is of great im- 

 portance ; for no matter how exactly suited to the nature 

 and wants of a plant are the mechanical and chemical 

 conditions of the soil in which it is planted, the heat and 

 water with which its roots are stimulated and fed, if 

 the heat and water of the atmosphere are either too great 

 or too little for healthy action. So much is this a matter 

 of importance, that were we to take the most elaborate 

 treatise on the cultivation of any given plant or fruit, 

 and expunge from its pages all the rules and precailtians 

 about atmospheric heat and moisture before placing it in 

 the liands of a beginner, what a great gap would be made 

 in the rudiments of culture ! The most elaborate direc- 

 tions might be given on the construction of the forcing- 

 house, and the character of the ingredients which should 

 compose the soil in which a Peach or a ^'ine will grow 

 most satisfactorily ; 5'et without some definite rules for 

 guidance in the matters of atmosplierie heat and moisture 

 to be maintained at the different stages of growth, the 

 inexperienced would to a large extent be in the dark, and 

 disaster would be sure to follow. 



By means of cheap glass and the ever-growing compc- 



No. "85.— Vol. XXX., OU) Sekieb. 



