The Newtown bee., 1896-03-20
H. N. AIRES
 381 Man St., Bridgeport,

34 pounds over the r. pounds If outside
 pressure. Thtre is therefore this tenden- cy of moi-turc to pass either way as the
 case may be to restore the equilibrium, when the tree is in the zero state.
 If certain conditions produce pressure,
 then reversed conditions must produce
 suction, the opposite condition. When
 the tree is in neither, in pressure or sue
 tioD, it is in zero. h good sap weather.
 as a general law, if is in pressure during the day and suction Ut right. In poor
 sap weather zero conditions prevail Pressure. What is fl? We can cnly understand it by knowledge of the in- terusl m>kc up If the ttee. IC is sup posed that there are many millions o4
 cells in every cubic inch of maple wood. These cells are supposed to be like small
 boxes, " ith covers, piled one upon anoth-
 CT, 90 that there are two partitions be-
 tween every box UT cell. These cells are
 filled with gases, air aud water, tngcth
 CT with soDe other materials or elements.
 Now we are prepared to understand the
 philosophy of the pressure. As the sun
 warns up the outside of the tree, the air and gases expand in all the cells so
 warmed up, occupying larger space, so that the pressure must be proportiolate.
 It is net so much the expansion of the cells as 1T is their expansible contents, and this expansion prcduces the pressure.
 Now if a small maple tree be scraped so as to remove the bark, the sap is forced out so the whole surface of wood is covered with tiny drops, showing what is taking place all over the surface. If then a tree is bored the pressure is re- duced so much. As a cool night comes on these expansive elements are contract ing, thus producing sort of vacuum, aud the pressure changes to suction.
 As to the methods of tapping trees. Iu New Hampshire, where in 1893 two and one quarter million pound of sugar were made, the state experiment. station has made some experiments N hich are of val ue to those who do it for a source of in- come.
 In 1892 a series of experiments lasting three years were made. It was found that the sunny side of the tree should be tapped as the warmth of the suns rays would soon produce a condition of pres sure and the sap would TUT, while on the the opposite side, the condition would be that of suction and no sal would run.
 It has been said it made no difference 1 as to the depth of the hole for the tube 1 Of two trees tapped one at one and three l quar ter inches, three and one half inches, l more than twice as much fl owed from | the deeper tapping. Where holes of one and one quarter inches were deepened to two and one-half, the increased flow was very marked. In another tree bored two inches deep with an inch bit, and the hole bored two inches deeper with smaller bit, the fl IVY from the in- ner wood was greater than from the out er though only one-half as large.
 In four trees tapped the flow from the nner wood of the if St tree bored two md seven eights inches was greater than from the outer wood. h the second nearly double that of the outer. In the ,ourth where the hole was six inches Ieep and one quarter inch in diameter he flow was equal to that of those where the hole was several times larger ,ut not so deep.
 The results Of these experiments led Q the conclusions that the tiow of sap i. cry largely dependant upon the depth # the tapping, aud the theory that all r nearly all the sap came from tha out T wood is erroneous. The additional 1inrv to the tree from the deep tapping ] very sligbf, especially if the hole Is mall. Where 2 three-eight bit is used