818 



BOSTON, WEDNESDAY EVEMM;, APKIL 15, 1830. 



NEW ENGLAND FARMER, 



APaiL 13, J833. 



FARMERS ^VCRK. 



To manage pasture land advantageously it sliould be 

 veil fenced in small lots of four, eight or twelve acres, 

 according to tlie largeness of one's farm and stock And 

 these lots should be bordered at least with a row of 

 trees. It is best that trees of some kind or otlior should 

 be growing scattered in every part of a pasture, so that 

 the cattle may never have too far to go in a hot hour to 

 obtain a comfortable shade. The grass will spring earli- 

 er in lots that arc thus sheltered, and they will bear tlie 

 drought better. But too great a proportion of shade 

 should be avoided as it will give a sourness to the 

 grass. 



Small lots thus sheltered, are not left withoutsnow so 

 early in the spring as larger ones lying bare, as fences 

 and trees cause more of it to remain on the ground. The 

 cold weather in March and April hurt the grass much 

 when the ground is bare. And the winds in winter will 

 not suffer snow to lie deep on land iliat is too open to the 

 influence of wind,? and storms. 



It is hurtful to pastures to turn in cattle too early in 

 the spring, and most injurious to those pastures in 

 which the grass springs earliest, ae in' low and wet 

 places Potching such land in tlie spring destroys the 

 sward, so that it will produce less grass. Neither should 

 cattle be let into any pasture, till the grass is so much 

 grown as to afford them a good bite, so tliat they may 

 fill themselves without rambling over the whole lot. 

 TheaOthof May is early enough to turn cattle into 

 almost any of our pastures. Out of some they should 

 be kept later. The dryest pastun>3 should be used iirst, 

 though in them the grass is shortest, that the potching 

 of the ground in the wettest may be avoided. 



distance before a concave glass mirror, the frigorific 

 rays falling on the mirror are reflected and brought to 

 a local point: A thermometer placed in the focal point 

 mediately sinks several degrees To prove tliis sink- 

 ing to be tlie eftect of the reflection of the frigorific 

 rays, place a cloth before the mirror to prevent reflec- 

 tion, and the thermometer rises several degrees. If 

 this be admitted, we need not wonder, why it is colder 

 in the valleys, in the absence of the sun and the atmos- 

 phere at a low temperature, than on the hills, nor why 

 the thermometers so often vary when suspended in dif- 

 ferent places. On the principles of reflection the val- 

 leys will be warmer in the summer than on the hills, 

 and in winter, in the absence of the sun, the valleys 

 will be colder than on the surrounding hills. 



Respectfully, ° r. Grlen. 



Mnnsfidd, March, 1835. 



I IFt ERENCK OF TEMPERATURE BETTVEEIV 

 IIILILS AlVD VALLEYS. 



Mk Fessenden— In the 27th number of the present 

 volume of the IN. E. Farmer, there is a query, " relative 

 to the cause of its being colder, when the atmosphere 

 is at a low temperature, in valleys than on hills." — 

 That it is colder in valleys than on hills in the absence 

 of the sun and the atmosphere at a low temperature is a 

 fact ; but the cause of it is the question. 



I have never yet seen any general theory of lieat and 

 cfld, that has been perfectly satisfactory, nor can I say 

 anything respecting these two great and powerful 

 agents very satisfactory to myself; but I hope that you 

 or some of your correspondents will do the .subject 

 justice. 



Cold and heat are called relative terms. I have 

 long been of the opinion, that cold or the sensation of 

 cold depends, more or less on some peculiar action (not 

 rightly understood) of the frii^vrific principle, what- 

 ever It may be.— Cold is not only called a relative, but 

 a negative term, implying the abstraction of heat. But 

 is this perfectly correct i Are there not radiation or 

 proiiulsion, reflection and absorption of the frigorific 

 principle .' The evidence that this is the case stands on 

 the same ground as the corresponding actions of the 

 calorific principle— determined by the rise and fall of the 

 thermometer. More or less of the heat in summer is 

 from the reflection of the sun's rays; and may not 

 much of the cold in winter arise from the same cause — 

 reflection of the frigorific rays ? AI. Prevost acciden- 

 tally discovered the reflection of cold some years since, 

 .and the fact seems well established. 



A quantity of ice, say &00 pounds, placed at some 



Bv THE Editok.— There are few if any subjects 

 more complex, or which have given occasion to more 

 division among philosophers, than the nature and prop- 

 erties of caloric, or the cause which produces the sensa 

 tion of heat. Some hold that calorie is material, exist 

 mg in the form of a subtle, all pervading fluid ; and 

 others that it has no independent existence, but is a 

 property of matter, requiring certain conditions for its 

 developement. The greatest number of modern philos- 

 ophers and chemists have maintained that caloric is 

 material, but the advocates of the opinion that it is a 

 mere modification of matter were many of them very 

 able, such as Lord Bacon, Sir Isaac Newton, Count 

 Rumford, Sir Humphrey Davy, &c. &c. 



Among other methods to ascertain whether heat is 

 matter, and of course a gravitating substance, attempts 

 have been made to weigh it while in, or surrounded 

 by air. For instance a cannon ball has been weio-hed 

 cold, and then hot in the same balance ; but it was found 

 that the acquisition of caloric gave no increase of 

 weight to the ball. But heat may possess weight, and 

 still be a thousand times lighter than air, and how can 

 we weigh a light body, surrounded by a heavier body. 

 Attempts to weigh heat, surrounded by air, appear to 

 me like essaying to weigh cork under water; and after 

 weighing the question we incline to the opinion that 

 coloric is as hona file material as lead or platinum. 



If heat be material it does not necessarily follow that 

 cold is negative, produced only by the absence of caloric 

 Still there are reasons wliich led us to believe that the 

 correct definition of cold is the absence of heat. What 

 is called" reflection of frigorific rays," may be account- 

 ed for by the absorption of calorific rays. The experi- 

 ment of M. Prevost alluded to above by Dr Green was 

 repeated by M. Pictct, at Geneva, with thesame results ; 

 but the latter concluded that it afforded an additional 

 proof of the radiation and reflection of caloric, but did 

 TWt imply that there was anytliing poi'/ijrc in cold. 



Profij.ssnr Turner accounts for the results of those 

 experiments as follows : " If a metallic ball in the focus 

 of one mirror, and a thermometer in that of the other 

 are both of the same temperature as the surroundino- 

 objects, (say GCj the thermometer remains stationa- 

 ry. It does indeed receive rays from the ball, but its 

 temperature is not affected by them, because it gives 

 back an equal number in return. If the ball is 

 above (JO degrees, the thermometer begins to rise, be- 

 cause it now receives a greater number of degrees than 

 it gives out. If on the contrary, the ball is below CO 

 degrees, then the thermometer, being the warmer of 

 the two bodies, emits more rays than it receives, and the 

 thermomeler falls. " 



In speaking of ice placed in the focus of a mirror in- 

 stead of a metallic ball, Professor Turner observes, 



" As the thermometer gives more reys than it receives 

 in return, it must necessarily become colder. It rises 

 again when the ice is removed, because it then receives 

 a number of calorific rays, proceeding from the warmer 

 surrounding objects, which were intercepted by the ice 

 while it was in the iocas."— Turner s Chemistry, p.p. 

 25, aO, Philadelphia Edition. 



In a room of a temperature, suppose CO degrees, a 

 body of 33 degrees will receive caloric rays, and a body 

 of say 212 degrees will communicate calorific rays, and 

 a thermometer will be afl'ected according as its position 

 is more or less favorable for intercepting and receivings 

 such rays. Addison says, somewhere in the Spectator, 

 that some philosophers supposed that darkness was 

 caused by " tenebrific stars," and not by the absence of 

 light. But we allow darkness to be merely negative > 

 and if darkness is caused by the absence of light, why 

 not cold by the absence of heat.' 



[Forlhe Now England Farmer] 

 KKITTIKG MACHIJSE. 



Mk Editor— Allow me to call the attention of the- 

 public to amachinefor knitting stockings and other knit 

 work, to be seen at the Agricultural Warehouse, No. 52 

 North Market st. It is a small neat, operating machine 

 by which persons in indigent circumstances, and child- 

 ren may be employed to great advantage, and it opens 

 a good field for the investment of capital. It occupies 

 about a cubic foot and is operated upon by turning a 

 crank, which requires no more power or skill than a 

 common hand organ, except when necessary to widen 

 or narrow, a stitch is dropped or added by hand. The 

 machine does the work of six expert knitters, and is 

 very simple, and does its work with astonishing rapidity 

 and precision. It is superior to the stocking loom, as 

 that requires an apprenticeship to learn to work it, and 

 is not calculated for families, whereas this machine can 

 be worked by any intelligent little girl, after a few 

 minute's instruction. It is capable of knittincr either 

 wool, cotton, silk or linen. The overseers of all pubhc 

 institutions are particularly invited to examine it, as it 

 maybe very advantageously employed by them, and is 

 within the means of the poor generally. 



Meeting of Wool Growers. — A meeting of anu.m- 

 ber of the wool growers of the County of Franklin, was 

 held at Shelburne Falls on the 27th ult. A correspond- 

 ing committee of 11 members was appointed, who were 

 requested to ascertain the number of fleeces raised for 

 the market in their respective towns, and to report at 

 an adjourned meeting on the 20th of May next. The 

 Franklin Mercury states, that the proceedings of the 

 meeting are preparatory to the establishment of a gen- 

 eral wool market, to be held in some central place in 

 the wool growing districts. 



A Philadelphia paper says, " The peaches are done 

 for' in Maryland. The cold weather froze up the buds, 

 until all vitality left them." 



MASSACHUSETTS HORTICULTURAL SOCIETY. 



KEOWERS EXHIBITED. 



Fnturdav, April 11th. 

 By Robert Rogerson ; fine specimen Lilium candi- 

 dum. 



By Messrs Hovey & Co. ; Superior specimen of tha 

 Ilyacinlh Gen. Washington. 

 By S. Sweetscr; a variety of fine specimens. 

 For the Committee. 



JoNA. WiNSHip, Chairman. 



