AMERICAN NOTES.

AMERICAN NOTES.

A plank has been manufactured at Elk river, Humboldt county, California, for exhibition at the World's Columbian Exposition, 16 ft. 5 in. wide and 12 ft. long, being 4 ft. 5 in. wider than it is long,

A cedar tree on J. M. Hockett's place in the Kalama valley, in Montana, is 18 ft. through and 350 ft. high. Whole townships of land in that section are covered with fir trees which are from 250 to 350 ft. high. The Cowlitz Bulletin says one of the resi dents of that locality built a house 22 by 30, one and a half stories high, and a barn 25 by 36 ft. from one tree and had piles of lumber and fence posts left.

In British Honduras camps are formed for mahogany logging at the beginning of the dry season. Experienced men select the proper trees, which are felled, hewed into shape and the floatable logs are cast into the rivers and streams to be carried to the sea. The dye woods will not float, and are consequently transported in crates. The methods employed in getting out timber could be improved upon, but are at the same time very good, labour being abundant and the appliances simple.

On account of the hard work required in cutting mahogany trees close to the ground,the natives direct their axes to a point from 6 to 8 ft. above it, leaving an average of probably from 300 to 500 ft. of the best part of the tree, so far as beauty of grain is concerned, on each stump, besides the roots, which are gnarled and twisted, and bear the same proportionate additional value to the body of the tree that a walnut root does, being admirable for veneers. The bottom of the tree is wide and spreads out. Two thousand feet is a modest estimate of the amount secured from an average trunk, irrespective of the waste.

A tree lately cut in Honduras made three logs, which were sold in Europe and brought over 11,000 dolars. The mahogany tree ranges from 1 to 7 ft. in diameter, is often 60 ft. to the first branches, and frequently exceeds 90 ft. in height, the cedar averages about the same in diameter. The Honduras mahogany comes to market in logs from 2 to 4 ft. square and 12 to 14 ft. long, planks sometimes being obtained that are 7 ft. wide. Its grain is open, and often irregular, with black or grey specks. The veins and figures are often very distinct and handsome, that which is of golden colour and free from spots being considered the best. It is said to hold glue better than any other wood. The weight of a cubic foot of mahogany varies from 35 to 50 lbs. As compared with oak, which is called 100 per cent., the strength of mahogany is between 67 and 96, its stiffness is from 73 to 93, and its toughness from 61 to 99 per cent. The dye woods are generally small, and are cut into small pieces. The Government

engineer of Honduras estimates the total value of the trees, such as are regarded fit to be cut, at 200,000,000 dols., while the smaller trees not ready to cut are also worth a large amount.-(Ibid.)

SAWS.

SWAGE SETTING, SPRING SETTING, HAMMER SETTING.

BY POWIS BALE, M.I.M.E., A.M.I.C.E.

In very few things is there more difference of opinion that in sharpening and setting saws. On the present occasion we propose to discuss briefly the different methods of setting, noticing some of the advantages and disadvantages of each method.

SWAGE SETTING.-Swage setting-called also "upsetting," "jumping," and " spreading "—is more largely practised in America than in this country. In this case clearance is obtained for the saw by widening the points of the teeth usually by means of a crotch punch arranged with two V notches, which are driven on to the points of the teeth by a hammer or weight. The second notch in the punch is rounded and spreads the teeth points out, We think this plan, especially for circular saws of stout gauge has much to commend it, more especially if the wood is crossgrained and knotty, as swaged teeth will stand up to the work, while spring-set teeth are apt to dodge the knots. Swage-set teeth will also stand a quicker feed than spring-set, all things being equal; they, however, take more power to drive-probably about 20 per cent.-and unless the setting is carefully done, ridge marks are left on the log. I think swage setting is, on the whole, more adapted for soft than hard wood.

It is claimed by the users of swage-set teeth that swaging condenses and hardens the steel at the points of the teeth; but, if this is so, with saws correctly tempered it would, I take it, be likely to be detrimental and cause the points to crumble. Another trouble found in swage-setting is the difficulty of getting perfect uniformity of set without which no saw can be pronounced to be in first rate cutting condition. Swage setting does not sharpen the teeth of the saw, as some may suppose.

When a saw is set or spread by means of a punch and a blow from a hammer, care should be taken that the points of the teeth only are spread, and that the tooth itself is not bent or strained, and that the blows given and the hammer used are not too heavy. The teeth should be carefully tried with a straight edge on both sides and points, aud be exactly in line. In swage setting, should a tooth point be broken by striking a nail, it can be lengthened slightly by raising the punch or swage when in the act of setting the tooth, and the point of the tooth will be upraised, and, if not too much broken, will take its share of duty with the rest.

To" spread" set all the teeth as nearly as possible alike with a crotch punch it is necessary to regulate to a nicety the weight or strength of the blow given by the hammer. In America a tool has been introduced to do this mechanically. It consists briefly in mounting the crotch punch on the end of a tube or rod, and arranging a series of movable weights, with holes through them, to slide up and down the rod. These weights are allowed to drop on the punch, the strength of the blow being regulated according to the gauge of the saw and the amount of set required. For saws of large diameter and thick gauge, spread set can be recommended, as it is very difficult to spring set or bend the teeth of a thick saw with regularity.

SPRING SETTING.-This is perhaps the most general kind of setting, and, if regularly and carefully done, answers very well; the teeth, however, have a constant tendency to assume their original position. Saw teeth should not, under any circumstances, be set without a gauge, as it is a wasteful and stupid plan, producing rough work and more rapidly wearing out the teeth which happen to be overset. In practice it will be found that a saw perfectly set will work much freer, cut smoother, and at the same time it will waste less wood than an imperfectly set one; less set is also required on a truly and equally set saw to effect the desired clearance.

Several good mechanical saw sets, combined with gauges, are now made, and so arranged that when they are fixed to any desired set it is impossible to overset a tooth; consequently the teeth are all set exactly alike, and, if they are equal in length, each tooth gets its fair share of work, the friction of work and waste of wood of wood being reduced to a minimum. In working it is found that the teeth of a saw wear at the side of the points, and if some teeth have more set than others, these are unduly strained, and, from the severe and uneven friction, are often heated, and are inclined to buckle and run from the line. In using spring set, it is necessary to somewhat overset the saw, to compensate for the tendency of the teeth, especially when worn or dull, to spring back to their original position.

We have recently seen a very neat form of American tool for spring setting by means of a cam-lever, by which a very even set may be obtained without unduly straining the saw teeth. The operator stands behind the saw, and the set is attached to the teeth by placing a bed die on the point of the tooth to be set so that the point will project beyond the die about one-sixteenth of an inch; the cam-lever is then brought down to a stop on the cam, at the same time bending the teeth towards the latter. A fourpoint gauge is fitted to the lever, and it can be adjusted to any amount of set desired by means of a thumbscrew. It is claimed as an advantage of this arrangement that the bending power is exercised on the tooth between two bed bearings, so that the operator has only to bear down on the cam-lever, and the more power

he applies the tighter he fastens the set to the saw, and at the same time the bend is a curve and not an augle, and that, therefore, the saw teeth are less liable to fracture.

If a saw is allowed to get dull it will spring from the work, and increased power will be required to force it through the wood.

HAMMER SETTING.-The third system of setting we have to notice is hammer setting. The old-fashioned way of doing this was with a punch and a block of wood, and a very brutal way it was, as it strained the saw plate, and sometimes broke the teeth; at the same time it was impossible to get the teeth to one unifrom set, consequently the timber was scored and much power consumed unnecessarily. If carefully and judiciously done, hammer-set saws will stand up well to their work. The best plan with which we are acquainted is to mount the saw horizontally on a conical centre aud allow the teeth to rest on an adjustable steel die made with a bevelled edge turned eccentric, so as to allow of the right proportion of set for teeth of various sizes. With this arrangement any desired amount of uniform set can be given to the teeth without unduly straining them or the saw plate. Hammer setting is a fair test as to the quality of the saw as the teeth may crack or fracture if the steel is burnt or of too hard a temper, or bend readily if too soft.

In conclusion, it must be borne in mind that, whatever kind of setting is employed, for successful and economical working absolute uniformity is imperatively necessary. If this is not secured, the work turned out is of inferior quality, and wood and power are wasted. It should also be remembered that setting does not increase the cutting power of a saw, as a saw will cut faster with little or no set provided the nature of the wood will allow it to pass through without binding. The amount of set required, therefore, should be carefully judged by the sawyer, and no more set employed than is absolutely necessary. For instance, in sawing wet wood a sharp saw and a fair amount of set are required, whilst for hard, knotty wood very little set should be used.- Timber Trades Journal.)

THE "KITTUL" PALM OF CEYLON.

THE "Kittul" Palm of Ceylon, so valuable to the natives of the South-Western and central portions of the island, from the richness of the juice of its flower spathes in sugar, we have always regarded as not only curious but remarkably handsome in its scolloped foliage. The American publication "Garden and Forest" dealing with palms for conservatories, has the following passage: Some of the "Fish-tail Palms" or Caryotas are very

KITTUL

useful and highly ornamental as small and medium sized plants, though they rapidly attain such proportions, when under suitable treatment, that they are not suited for all collections. Of the Coryotas the most common and easiest to procure are C. urens and C. sobolifera, both of which are good and also easy to manage, as they germinate from seed readily and in a short time and make rapid growth. Caryota urens throws up its handsome leaves on strong stems, and in a large plant they sometimes reach a length of twelve feet or more. The leaves are bi-pinnate, which is an unusual characteristic among Palms, and the pinnules are more or less wedge-shaped being from six to eight inches in length and about half that measurement in width. The ends of the pinnules are erose, this giving them an odd appearance and readily suggesting the common appellation of Fish-tail Palm, while the color of the leaf is dark green. Another peculiarity of C. urens is the manner in which it flowers though this process does not begin until the plant has attained its full size. It begins to flower from the centre of the top of the stems, after which the flowerspikes are produced in a succession downward nearly to the base of the trunk until the vitality of the plant is exhausted. The seeds are somewhat larger than a Bush Bean, dark brown in color and quite hard, this description applying to the seed proper after the outer fleshy rind has been removed. C. sobolifera is also a fine plant, and is more dwarf in growth than the preceding. It also has bipinnate leaves, which are bright green in color, and as it throws up suckers at the base of the plant, it naturally has a more bushy habit than C. urens. Other good representatives of this genus are C. furfuracea and C. Rumphiana, both of which are good decorativa Palms. Acanthorrhiza stauracantha, sometimes known as Chamerops stauracantha, is another fine Palm which will succeed in a moderate temperature. It has palmate leaves, deeply divided and dark green above, while the under side is covered with a silvery tomentum. A distinguishing feature of this plant is the mass of root-like spines which surround its base, and from which its generic name is derived. It is a native of Mexico, and though not very common, has been in cultivation for many years. (Indian Agriculturist, June 11th 1891).