Ever Since the establishment of gas Works it has been considered a matter of great impbftpnee to find some useful application fdr their waste products, principally the coal tar The old custom was to use wood tar as a coat for common wood structures exposed to the inclemency of the weather, and it was Soon found that coal tar resinifies, dries, and hardens quicker than Wood tar. This circumstance led to experiments to ascertain the preservative nature of coal tar. More than fifty years ago W. H. Hyett and others impregnated wood with gas tar, and reported that cuch wood, placed in a damp cellar, became moldy sooner than the same wood in its natural state, and that it showed fungi, particularly where the tar abounded. In 1830, Reichenbach published Ms experiments, by which he obtained creosote from beech-wcod tar. He subj ected the tar to a fractional distillation, the heavier products, which distilled over by increased heat, were washed with an alkali, redistilled, again treated with lye, and then with sulphuric acid, and again distilled. The substance so obtained he found to preserve meat, and therefore called it " creosote," meaning-meat preserver. This invention of Reichenbach served as a nueleus for a number of erroneous conclusions. It was alleged that a sub stance which preserves meat also preserves wood, which is not true. A solution of common salt, for instance, serves to preserve meat and fish, while it accelerates the decay of woocJ It was said that coal tar is the same as wood tar, and fur nishes creosote, but the truth is, coal tar differs materially from wood tar, and contains no creosote. It was further stated, that the mere distillation of coal tar is sufficient to convert the same or part of it into creosote, and the coal tar, which distilled over by increased heat, and was found heavier than water, was deceptively called "creosote," sold as creosote, and used as creosote to "creosotize" wood and preserve it yielding, through such misrepresentations, large revenues to the gas works and inventors of various processes to impregnate wood with gas tar or its products. The first man whom we find engaged in the creosotizing patent business, and probably the most candid inventor, was Franz Moll in A. D., 1835. He found, by practical experiments, that the so-called " creosote of coal tar " was worthless to protect wood from decay. He ascribed its failure to the presence of other substances therein, with which the " pure creosote " is associated, and strongly recommends its previous purification with alkaline lye, similar to Reichenbach's process described above. When coal tar is heated in a still by gradually increasing heat, the product first obtained, which is lighter than water, is called by him " eupion," the heavier liquid obtained thereafter he calls "creosote." Merely coating wood or timber with coal tar or other tar, he finds of but little advantage. Moll's British patent was granted in 1836, and is the more interesting, as his process is based on the best principle, so far known, to saturate wood with liquids, and as his specification accounts for the necessity of tedious operations, without which he finds the application of the products of gas tar of no practical advantage. His process is as follows : The wood is placed in a close chamber, which is connected with one or more stills. He begins the operation by heating the inside of the chamber by a steam pipe or elsewise, to about 100 Fah., and then increases the heat gradually till sufficiently warm, to assist in maintaining the vapors of eupion and creosote in a vaporous state. The water from the damp timber is then drawn off, and eupion, previously sufficiently purified, is heated in the still, from which the vapors enter the chamber. When the wood is considered sufficiently impregnated with the eupion vapors, the surplus vapor is drawn off, and vapor from a still containing creosote, also previously purified, is then admitted, and finally boiling liquid creosote is introduced into the chamber by a pipe in a quantity sufficient to cover all the wood therein. After the whole has become cold, the wood is removed from the chamber. He describes the following experiment, made by him "on balk of good oak which was rather in a damp condition, thS same was fourteen inches square, and about ten feet long, which, on being submitted to the vapors of eupion for about six hours, when cut in two parts, was found to be impregnated proportionately, even to the heart, with eupion, and when the two parts were afterward submitted to the vapor of creosote, and boiling creosote, the same was found to have taken effect within 12 hours. But subsequent experiments have proved that it is better to submit the wood or timber for a comparatively short time to the action of the vapors of eupion and creosote, and depend more on the liquid bath, as described, this process being less liable to crack the wood or timber than the vapors." MOLL's SIMPLIFIED PROCESS. " Where it is not thought a matter of importance, whether the timber be chiefly penetrated with creosote or eupion, the former of which I consider th chief agent against dry rot, or where the operation is chiefly performed in order to prevent the effects of penetration of water into the wood, or where it is judged to be immaterial, whether these fluids convey any acidity into the timber, and when the proportion of eupion and creosote contained in the tar is well known, the operation may, of course, be much simplified by letting the vapors or liquid products of tar, or other matter containing eupion or creosote, or both, enter into the timber. But I am bound to state that the above-described method of washing the substances, and applying them separately, will be found far superior in use, as the volatility of the eupion and its fluidity will allow its rapid penetration into the timber more perfectly than when in combination with the cresote, whose entrance 375 the former will greatly facilitate when once lodged in the pores through the affinity of the two substances, and as by these means the quantity of eupion can be regulated which is to be absorbed by the wood ; moreover, the antiseptic power of the creosote will be augmented by the washing and freeing from matters mixed with it." LOUIS S. ROBBINS' PROCESS. The process just described by Moll as his simplified operation, was reinvented thirty years thereafter and patented here, A. D., 1866, by Louis S. Robbins, of New York, and the patent was lately purchasedby "The National Patent Wood Preserving Company," by whose order a pamphlet was published last year under the title of " Discovery of a Lost Art of the Egyptians." Robbins, like Moll, uses a chamber, in which the wood is placed; Robbins also uses a retort, or still, in which, like Moll, he heats coal tar and introduces the vapors from the retort into the chamber by a gradually increasing heat, lets off the water from the damp wood, and impregnates the wood with the vapors of coal tar, which he calls " oleaginous vapors," while Moll calls the same " eupion and creosote." Robbins says further, that he does not limit himself to any particular form of apparatus, nor does he intend to limit himself to the removing of the surface moisture from the wood by means of oleaginous vapors, as there are various ways in which the same can be accomplished with the use of heat. " But what I claim as ' new' is the process consisting in first removing the surface moisture from the wood and then charging and saturating the same with hot' oleaginous' vapors and compounds, also removing the surface moisture from the wood by means of hot oleaginous vapors." We suppose that Robbins did not know of Moll's process, as he says in his specification : " From the above description it is apparent that by my process I am enabled to more completely saturate the wood with the preservative compound than has been, or can be done by any of the processes heretofore in use, for the reason that I cause the preservative compound to permeate the pores and fibers of the wood in a vaporized state, while in the others it is made to enter in a liquid state." JOHN BETHELL's PROCESS. Patented in England in 1849. He applies the " creosote," or coal tar, in its liquid state, without any previous purification. The wood is placed in a pressure tank, from which the air is exhausted previous to the introductionof the "creosote," which is then forced into the pores of the wood by a pressure pump. Bethell's process, being the most simple and quickest in its operation, was extensively used, and of the results we have reliable reports. David Stevenson, the eminent English engineer, states that although highly recommended to him by Bethell, he found such creosotlzed wood to be wholly unfit for use on piers or other water structures, as it was soon destroyed, perforated, and eaten off in places where the creosote abounded, though the most favorable location had been selected for trial, and every precaution used by Bethell in the preparation, the wood having been creosotized after being cut into the shape in which it was applied, (Civil Engineer and Architects Jowrnal, vol. 25, page 205. London, 1862.) Wm. Jerry Walker Heath reports (ibidem, vol.29,page 301. 1866) that square rail ties sent by Bethell for use in South America, even when laid on the best sandy ground, were soon totally destroyed. John Bethell himself stated (ibidem, vol. 29, page 823) at a meeting of the association of the engineers, that he received from Belgium rail ties of the round shape back, which were previously creosotized by him in the best manner, and which were then found to be hollow like a cannon, the heart being all gone, and the outer part representing a black, hard mass. FAILURE OF COAL TAB OIL FOR THE PRESERVATION OF WOOD. The causes of the failure are explained by the fact that coal tar does not yield any creosote, even if treated in like manner as wood tar, which often yields as much as 25 per cent of creosote. The substance obtained by the treatment of coal tar is carbolic, or phenic acid, which differs materially in its properties from the real creosote. Being an effective disinfectant, carbolic acid does not prevent fermentation nor purification; on the contrary, Ilisch, of St. Petersburgh, found that some substances impregnated with a solution of carbolic acid showed the formation of mold within a fortnight. This circumstance, taken in connection with the fact that coal tar resinifies and hardens quicker than wood tar, explains the failures observed by Hyett, Stevenson, Heath, and others, when used in a wet place, where the tar cannot quickly dry and form a hard coating. This also explains why nothing but a hard mass outside remained in the rail tie spoken of by Bethell, where all wood within was gone, leaving the resini-fied tar as the " hard, black mass." Such is similar to the experience of coachmakers relative to hubs, which, when painted with oil color before being well seasoned, soon rot on the inside. Experience and science seem to teach that the use of coal tar or its products is, in most cases, more detrimental than advantageous for the purpose of preserving wood. Women as Farmers and Cattle Breeders. At the annual meeting of the Northwestern Dairymen's Association, held in Elgin, 111., on the 9th and 10th of February, the Hon. K. A. Willard, of Herkimer county, N, Y., made an address from which we extract the following: Mr. Willard said he did not mean to advocate female field labor, such as is known among the lower classes in Europe, nor would lie abridge one iota any female accomplishment; but he could see no objection to any man's daughter or sister taking her seat occasionally on the mowing machine, the hay tender, the wheel rake, the sulky plow or cultivator, or in the direction of some light farm machinery, where she can gain strength and health in the open air. He was confident women enjoy such things, and are much happier, stronger, and better, if they are taught that such work is not unwomanly, and the knowledge gained would be of immense service in after life, in assisting the father, brother, or husband with suggestions and advice. In their education we do not give our girls a fair chance in the race of life. The majority of American boys and girls do not like to make a choice of farming as a livelihood. The farmer's educated daughters of to-day prefer the town or city, and have little sympathy for the farm ; and if they marry a farmer, often urge him to abandon the business for something more genteel. la England they have better tastes, where their women have more fondness for country life than ours. A well-bred English woman seems to take pride in the knowledge of business suitable to her station. Lady Pigott, tbe wife of Sir Robert Pigott, has one of the most noted herds of skort horns in England. She has made it both a source of profit and reputation. A high bred American woman can hardly understand such a taste, and regards it with intolerable disgust. He did not care to discuss this questien. He only asked that farmers try in some way to make farming pleasant and interesting to wives and daughters, that the farm may have their sympathy and influence, for without such help it is hard to make farming successful. The Rubbish in the Patent Office. "What rubbish!" is frequently in the minds, and not seldom on the lips, of those who daily throng the galleries of the United States Patent Office at Washington. A very little reflection will show to what a limited extent these but too carelessly-conceived thoughts, and these equally carelessly-uttered words, are just. .On the 15th of December, 1836, the General Postoffice Building at Washington was entirely destroyed by fire. In the upper portion of this edifice the United States Patent Office then had its home ; its scanty rooms being filled to confusion and repletion with models, drawings, and specifications, coming from the inventive mind of the nation, and deposited there from the time patents were first issued by our Government. These models, drawings, and specifications were all destroyed with the postoffice building; ashes and melted or twisted fragments of copper, brass, iron, and steel being all that was left of that which had often been looked upon with a feeling akin to wonder by the thoughtful—wonder that so much time, thought, and money had been spent in elucidating and preserving plans and schemes (many of them could not be called inventions), never heard of, noticed, or seen outside of the rooms in which they had found a legal home. Since the disaster of 1836, a new and spacious building, one of the striking ornaments of our national metropolis, has been erected for the use of the patent office; and this building, with a current issue of about three hundred new patents per week, is now filled almost to its utmost capacity with models of nearly every conceivable form and for almost every conceivable purpose. How comes all this strange medley 1 this aggregation of odds and ends? and what are their ttses? Man might be called a blundering animal, not guided by the unerring instinct that prevents the lower animals from making a mistake ; not satisfied to follow the beaten track, he tries different modes of doing the same thing, often blundering most glaringly, but sometimes, in the result, reaping a full reward in fame and fortune by hitting upon and bringing out something invaluable to his fellow-man. Slow, and even .obstinately unwilling as we are to change from old to new ways, " Let well enough alone," and, " It is good enough as it is," have been deeply fixed in our natures from the beginning. Hence, innovators have never met with favor, and instead of being helped and encouraged, they are but too often sneered at and hindered even by those who are most likely to be benefited by their labors. Many a really valuable invention or improvement has been persistently resisted and opposed at first by the very persons who, in the end, are to derive the most benefit therefrom; and ere a foothold could be gained, many a battle has been fought for years, against the most unfair odds, with those who should have been doing most to aid and assist in the advancement of the new idea. Even the workmen in charge of dangerous apparatus, and whose lives hang sometimes upon a thread, not only do not seek or care for greater safety, but they often persistently and willfully set themselves against the very thing they should do their utmost to help on as a good to themselves. It is a strange anomaly that it is in cases where life and property are most in jeopardy by defective modes of using some needed but highly dangerous thing, that the greatest apathy is felt; and those who thoroughly understand the question often make great opposition toward even a fair trial of a proposed improvement. On the contrary, most of what is seen at Washington is the work of men often with little or no experience in the particular branch they have taken in hand. It would seem from this that those most familiar with a subject, may not be best calculated to improve it, simply because they do not care to get out of the old ruts. Hence, the innovator, and sometimes improver, is most likely he who lacks almost all knowledge of what has preceded him. On the other hand, hundreds of patents are rej ected upon application, simply because an idea has been hit upon by the applicant quite new to him, and apparently valuable, but which, from some good reason, only learned by experience, has proved fallacious, and consequently has long ago been discarded. It would be well for those who profit by the real improvements that come from the teeming brains of those who fill the galleries of the Patent Office with their curious labors, to keep back their too-ready shrug and sneer when new inventions aro brought to their notice by some poor devil of a patentee, as innovators are but too often termed. Look at least with charity and consideration, upon a class to whom we owe so much. Help them when you can, and be not niggardly in kind words of encouragement, and with money, too, when you can do so out of your own excess. Remember that, since the time when man has needed anything, it is from just such men as these, whom you but too often discard unthinkingly, have come all the comforts we enjoy in our homes, in our business, and in every walk of life. To this ever-restless band we owe all of improvement that so strongly marks this epoch in the world's history. The minds of but few in the grand total of humanity have thus worked incessantly for our good, in the long past as in the present, and they should be treated, individually, and as a class, not as half-witted visionaries, but as the benefactors of our race. They have ever battled on against every discouragement and every hindrance, each, like the soldier in a forlorn hope, trusting that he might be the one to plant the flag on the parapet and reap the wished-for reward. The work of these men—these martyrs as they may sometimes be called—can never be really known. Its record would take in all the failures, and it would also take in that much larger aggregate of all the brain-worn hours, which have left no mark except that deep one on the weary mind of the thinker, who, after all his labor, finds that he has only succeeded perhaps in, as it were, proving a fallacy. But we can measure the value of the work done—of the wheat winnowed from this large amount of chaff—by what we see of success all around us; and by these fruits we should know them, and with this knowledge we should ever be jvilling to admit that those who have piled up the rubbish in the Patent Office at Washington, are worthy of more honor and more reward than they usually receive.—Lippincott's Magazine. The American Association for the Advancement of Science. This Association has issued a circular announcing that the eighteenth meeting will be held at Salem, Mass., commencing en Wednesday, August 18th, 1869, at 10 o'clock, A. M. For the general good of the meeting it is hoped that all who can will be present at the organization. On the afternoon of the first day of the meeting, the Association will be invited to participate in the dedication of the. Museum of the Peabody Academy of Science, followed by a levee in the evening. It will be the aim of the local committee to make the sojourn of the members of the Association in Salem pleasant, as well as profitable in a scientific point of view. The usual local courtesies will be extended. Special arrangements will be made for members wishing to collect marine animals for their cabinets. The committee is giving attention to the facilities for coming to and returning from the city over all routes of travel, and it is hoped that arrangements will be made with the railroad companies by which half fare will be secured for those attending the meeting. As the hotel accommodations in the city are very limited, special arrangements will be made with the proprietors of several boarding houses for the accommodation of members, and many citizens have signified their desire to extend the hospitality to members of the Association ; but in order that all may be provided for without confusion or delay, it is requested that persons intending to be present at the meeting, will notify the local secretary at as early a day as practicable, and when possible state the day they will arrive. The committee will engage rooms for those who request such an arrangement to be made on early notice being received. A prominent feature of the meeting will be the department of microscopy. The local committee, in order to give encouragement to the general and increasing interest in the use of the microscope, have decided to furnish rooms for the display and comparison of microscopes, objectives, accessory apparatus of all kinds, test objects, and objects of scientific and popular interest. It is intended to have as complete a collection as possible of instruments of both American and foreign manufacture. Those who are possessed of microscopic stands, objectives, or accessory apparatus, in any way remarkable for excellence of performance or design, are requested to bring them to the meeting. The objects of this exhibition will be to assist the progress of scientific research, by social intercourse and a full compari son and discussion of whatever is new and important in mi croscopical investigation, and to encourage the manufacture and use of this valuable instrument. New Process for Manufacturing Beet Root Sugar. The eminent French chemist, Payen, has recently communicated to the SociSte d'Encouragement, in France, a new and simple process for manufacturing sugar from the beet root, which has been successfully practiced during the last sugar campaign by Mr. Champonnois. It is as follows : The beet root is reduced to pulp by the ordinary process, and treated by the Perrier, Possoz, and Cail process of double defecation and carbonatation. After crystallization, the remaining sirups are reduced to a density of 1040, or about equivalent to that of the original juice. The temperature is then raised to 158 Fah., and this diluted hot sirup added to a second portion of fresh pulp. This is allowed to drip, and treated in the same manner as the first. A repetition of these operations is effected ten times in succession with new bodies of pulp and residual sirups. The sirups obtained each time are clear and limpid. The salts contained in the beet root, and a large portion of the nitrogenized substances are left in the pulp by coagulation and by dialysis during the application of this method. Improvement in Velocipede Wheels. Lightness and strength are two essentials in velocipede construction, and many otherwise meritorious inventions have failed to become popular simply because one, or both, of these points were lost sight of in devising them. The improvement which we this week lay before our readers, is one directed es- j pecially to securing these vital points, and will become obvious with a very brief description. The rim, a portion of which is shown at the upper right hand corner of the engraving is corrugated as there plainly shown. The spokes are inserted into the rim alternately on opposite sides of the groove in the rim; those inserted into the left lateral portion of the rimconnectingwiththe right end @f the hub, and those entering the right lateral portion of the rim joining with the left end of tlie hub, thereby supporting the , rim on both sides, and strengthening the wheel against lateral strains, at the same time admitting the easy attachment of rubber tire if desired. This form of the wheel gives very much greater strength and elasticity with a given weight of metal than could be attained by the old method. The engraving shows an improved bicycle "with the wheels constructed as described. The airiness and grace of the wheels are well delineated, thus illustrating the truth, that feeauty of design is always connected with perfect fitness in mechanical construction. In. fact the bicycle from which this engraving was taken, is a marvel of perfect workmanship, and reflects gfeat credit upon the manufacturer and inventor, Mr. Virgil Price, 144 (xreene street, New York city, whom address for further information. Patented through the Scientific American Patent Agency, May 4,1869.