\^' mmsymit.vmmm^:)mmmmmmi)'.^mmmam!x^ 



Some Pointers Concerning Glue 



It is seldom that as much real inforniation is delivered in so 

 small a package as that recently sent out by J. A. Taggart, Toledo, 

 O., in the form of an eighty-five page book on glue. The informa- 

 tion is primarily for the user, and deals with selecting, handling, 

 testing, and applying the article. It is, therefore, of interest to 

 a large class of manufacturers of wood commodities. 



The glue industry in America was founded by Peter Cooper in 

 1837. Its rapid growth began about 1880, at which time the 

 «nnual output was worth $4,000,000. It is now worth $15,000,000. The 

 capital invested in the business is not much short of $13,000,000. 



Animal glue is a by-product of packing houses. The usual parts 

 cf animals of which it is made are hides, bones, sinews, tails, 

 Bnouts, ears, piths of horns, tannery waste, shoe factory waste, 

 and the waste of button and knife handle factories that use bone. 

 Heads, tails, fins, bones, sounds, and other parts of fish are excel- 

 lent materials for the glue factory. 



The processes of nature do not make any glue: they simply 

 provide the substances of which it can be made, and man's in- 

 genuity has devised the methods of producing the completed arti- 

 cle. The operation is not complex, although a number of impor- 

 tant details had to be found out by experiments. The desired 

 result is produced by the action of water and heat on nitrogenous 

 substances. The details that must be learned relate to the amount 

 of water, the degree of heat, and the duration of the process. 

 After boiling there must be drying, and that must be carefully 

 and skillfully attended to. The user of glue is not particularly 

 concerned with the method of making — that is the manufacturer's 

 business — but the user will be none the worse for knowing some- 

 thing about the manufacture of the article about which he is so 

 'greatly concerned. 



The test of glue is in its use. There are grades and kinds, but 

 when a man wants a glue for a particular purpose, the safest 

 thing he can do is to try it out. Tests for determining quality 

 are physical rather than chemical. The laboratory man with his 

 retorts, acids, agents, and test tubes can find out many things, 

 but they do not mean a great deal to the man who is desirous of 

 knowing whether a particular glue will answer his purposes. He 

 can make a number of tests for himself, provided he has had 

 experience and knows his business. The quality depends largely 

 en viscosity — the flowing qualities. The slower warm glue flows, 

 other things being equal, the better it is. The rate at which 

 water flows is taken as a basis of measurement. The jelly test 

 is another method of determining quality. A light glass vessel is 

 Ijlaced on the surface of warm glue, and the vessel is gradually 

 loaded with shot, and note is taken of the rapidity with which 

 it sinks into the substance: the slower the better, other things 

 being equal. Some excellent judges of glue depend on the finger 

 test. Nothing but long experience will make a man proficient in 

 this process. The tip of the finger is pressed upon the warmed 

 surface. The depth and the character of the impression furnishes 

 a key to the glue's quality, but the interpretation depends on the 

 knowledge and skill of the man who makes the test. 



It is said that white bubbles, in the shape of round blots, on 

 the surface of glue is evidence of decay. Bubbles may appear 

 within glue — not on the surface — without being an indication of 

 putrefaction. A good glue is smooth though not necessarily glossy. 

 Sometimes the very best will be of a dull color. The surface 

 thould be uniform in color and appearance, but the color is not 

 important as a rule. A thin piece of cold glue, if of good quality, 

 will bend considerably before breaking, and this is one of a 

 number of tests that can be easily made. High-grade glues never 

 show glassy fractures, but bone glues do. If glue in solution is 

 beaten with an ordinary egg beater and shows foam which does 

 not quickly subside, the article probably contains impurities. 

 Experts say, avoid using any glue that does not smell sweet and 

 clean. 



As much depends on right methods in the glue room— where 



— 3-.'— 



the glue is used — as in the factory that makes it. In the first 

 place, the waste is said to be fully twenty-five per cent. Glue 

 should always be soaked in cold water before using. It should 

 be thoroughly dissolved before heat is applied. Good glue will 

 absorb from 150 to 250 per cent of its weight of cold water. 

 Flakes should be soaked ten or twelve hours, ground glue from 

 one to four hours. It must be thoroughly soaked, not merely 

 moistened on the outside. Only pure cold water should be used> 

 that from boilers should be avoided. 



In heating glue, the heat should be applied indirectly, ^ and 

 should not exceed 150 degrees. The glue must not boil, and live 

 steam should not be applied directly — it will ruin the glue. Vessels 

 in which the substance is dissolved or warmed should be brass, 

 copper, or aluminum, and the vessels should be frequently cleaned. 

 Too much should not be melted at one time. It must be protected 

 against dirt; too rapid evaporation; cold drafts, or a room toO' 

 cold must be guarded against. All surfaces to which glue is 

 ai^plied should be warm and dry, but each situation must be indi- 

 vidually considered, because the manner of applying is of great 

 importance and rules which suit one case may not work well in 

 another. Among rules laid down for the selection of glue are the 

 following : 



For wood joints use high test hide glues. They make strong, 

 firm joints, which is extremely important since joints are subject 

 to more or less tension; and they set rapidly. 



For veneers take a moderately high test mixture of bone and 

 sinew or bone and hide glue. The higher test glues set too 

 quickly for this particular kind of work. If a spreading machine 

 is used, avoid a glue that tends to foam. Sometimes foaming is 

 caused by spreading too fast. Overheating glue also tends to foam 

 it. This can be overcome by the addition of sweet oil, vaseline, 

 parafline, or wax candle, but it is objectionable when veneering. 



Somewhat "Chestnutty" 



Professor N. F. Davis of Bueknell College must have been mis- 

 quoted in a recent interview on raising chestnuts. According to 

 figures attributed to him there is more money in raising chestnuts 

 than in any other crop that grows out of the ground, when cost is 

 considered. It is stated that chestnut trees eleven years old aver- 

 age a bushel of chestnuts a J'ear, "which sell readily for from five 

 to ten dollars a bushel." That means from $559 to $1118 an acre 

 per year from the crop. It beats ginseng or Louisiana lettuce. 

 The professor figures on cutting the trees for lumber in "from 

 twenty to thirty years" and getting another profit. What would anj' 

 one want to cut trees for, if they produced from five to ten dollars 

 a year in nuts? A thirty-year-old chestnut tree would sell for only 

 a dollar or two as a pole or a few posts. Besides, trees that grow 

 chestnuts in considerable quantity never amount to much as lum- 

 ber, because only short limby trees bear chestnuts; tall ones- 

 produce only a few at the top. 



Unless the figures of production and profit in the interview 

 are accepted as a joke, there is danger that they will fool people 

 into planting chestnut in expectation of returns which will fall 

 about ninety-five per cent short of the estimate — as has been the 

 case where the catalpa and the eucalyptus crazes have led gullible 

 people to do foolish things. 



Use for an Unimportant Tree 



Efforts of enterprising furniture manufacturers in America to 

 sell wooden bedsteads in India encounter difficulties which arc^ 

 explained by Consul Henry D. Baker in a recent report. Hugs 

 eat up wooden bedsteads in that country. In America the bugs 

 generally are satisfied by eating the sleepers, and leave the bed- 

 steads. Why not try sassafras wood in making a sample lot of 

 bedsteads for the India trade? If this wood's reputation is not 

 founded on false pretenses, no insect will come near it. 



