BIG HEAD— EVAPORATION AND FILTRATION. 



277 



BIG HEAD. 



Mr. Editou: — la the JuuE number of the Farmer 

 I saw an inquiry in respect to the origin and treat- 

 ment of a disease in horses called the Big Head. 

 An effectual and tried remedy is, as soon as the swel- 

 ling on the side of the face appears, take six or eight 

 grains of white arsnic, wrap it in fine paper as small 

 as you can; malje an incision in the skin, immediate- 

 ly over the hard tumor, and insert the paper contain- 

 ing the arsnic, and with a needle and thread make 

 one stitch, tie the ends in a hard knot — bleed the 

 horse and turn him in good pasture, or, if the weath- 

 er is cold, put him in a stable, removed from other 

 horses, and feed him on light food. In about six 

 weeks the arsenic will have developed its efficacy; let 

 nature have its cpurse about one month longer, then 

 the wound may soon be healed by common applica- 

 tions for that purpose. James Ansley. 



Indiana Co., Pa. 



KAnr-EVAPOKATION AND FILTEAnON. 



We have before mentioned a paper, prepared for 

 the Transactions of the New York State Agricultu- 

 ral Society for 185-t, on this subject, by Hon. George 

 Geddes. From an attentive perusal of it, we find 

 it contains matter which would be very valuable to 

 the farmer. Meteorogical facts have not received 

 that attention from the agriculturist, and not until 

 recently from the government, that they deserve. 

 Mr. Geddes well remarks, that " One of the things 

 to be looked at in selecting a new home is the rain- 

 gauge, and the government would do the world a 

 great favor to have rain-gauges kept at all the fron- 

 tier posts, and at every station in the country, and 

 publish the reports, property arranged in tables, lor 

 every work." 



It has been ascertained from records kept in vari- 

 ous parts of Europe and America, that there is annu- 

 ally more rain along the Atlantic coast than in the 

 interior. But the wants of agriculture do not de- 

 pend so much on the quantity of water as on the 

 manner in which it falls. Thus, some districts which 

 in the course of the year receive an unusual quantity 

 of rain, suffer much from drouth. In England the 

 annual fall of water is stated to be 32 inchee. Along 

 the Atlantic coast of the United States it is at differ- 

 ent points from 38 to 40 inches, and in the State of 

 New York, taking the average from about forty 

 points of observation, it is 35 inches. Yet the cli- 

 mate of Britain is much more moist than that of the 

 United States. There the number of rainy days is 

 greater, and the rains more moderate than here. 

 There is also a great variation in different parts of 

 our own country. In the warmer and more level 

 portions, rains often come in heavy showers, washing 

 and packing the earth injuriously; in the cooler and 

 more mountainous sections there is a regular conden- 

 sation of vapor, and the rains fall lighter and in a 

 longer space of time. 



Some of the principles involved in evaporation 



and fill rat ion, are given by Mr. G. in the following 

 paragraphs: 



When the frost leaves the ground in the spring it 

 is full of water, and a cubic foot of this saturated 

 earth is to water in its specific gravity as five to 

 three; dried to the moisture suitable to have seed 

 put in it, it loses one-twelfth of its weight; when 

 perfectly dried it loses one-third. 



Mr. Dai.ton, in making his experiments, came to 

 the conclusion that when it had lost one sixth of its 

 weight by drying, it was not too dry to support veg- 

 etation. When it had lost two-ninths it appeared 

 like top soil in summer. Hence every foot of earth 

 in depth, so saturated, contains seven inches of water, 

 and it may part with a quarter of its water, or even 

 one-half, and not be too dry for supporting vegeta- 

 tion. This is the fund of water with which we start 

 in the spring — say three inches in depth, within one 

 foot of the top of the ground. Roots of plants go 

 down lower than this if the soil is mellow and not 

 flooded with water. 



Mr. Dalton's experiments, made with a cylindri- 

 cal vessel, ten inches in diameter, three feet deep, 

 filled with gravel, sand, and soil — having a discharge 

 pipe at the bottom, by which to measure the quan- 

 tity of water that runs off; and which gave perfect 

 drainage — the top of the soil being covered with 

 grats, the whole buried so that the top was even with 

 the ground, shows that earth that is moderately moist 

 will take up three inches of water without carrying 

 it beyond the point of saturation. This amount had 

 in the preceding dry month been taken up by the 

 plants and evaporated, and, without making the soil 

 too dry, had so drawn upon it that it could imbibe 

 three inches, which fell in four days. 



Ordinary plowing does not bring into use more 

 than six inches in depth of soil; extraordinary plow- 

 ing may reach as low as one foot. Subsoiling and 

 trenching to the depth of three feet would give to 

 the plants all that Mr. Dalton claims for his experi- 

 ments. AVhere ground is cultivated only six inchc'^ 

 deep, it only holds, subject to the purposes of vege- 

 tation, (if no account is made of water rising up 

 through the hard earth beneath), one inch and a h;iir 

 of water. If cultivation goes down one foot the 

 quantity of available water is doubled. If the soil 

 is broken up still deeper, though it may be that the 

 roots of the plants may not go down beyond a foot, 

 yet the water from lower down will rise up by capil- 

 lary attraction, and supply the evaporation from the 

 superior parts of the soil. So it results that while 

 one foot of earth will hold for the uses of vegetation 

 three inches of water, three feet will hold so much 

 that it can part (without becoming too dry) with 

 three inches, and then receive in the course of a lour 

 days' rain another thiee inches, without overflow or 

 discharging from the drains beneath. 



It will be noticed that in the estimates comprised 

 in the last paragraph, no account is made of water 

 rising from the earth below the depth of cultivation. 

 Now it is evident that whether water will rise from 

 below this or not, depends on the condition of the 

 underlying strata. It is well known that some soil 

 is naturally just in that state which favors capillary 

 action. Other soil is in a different state, and needs 

 changing, aitificially. Further along, Mr. Geddes 



