arranged in single rows in two machines. In the Davoll machine the same single driving shaft was combined with two sets of spindles, and performed the duplex function of driving the two distinct rows; but each spindle of each row spun its separate yarn and the operation of one spindle did not affect in any manner the operation of any other one, the number of yarns spun being produced by the separate actions of the spindles. The improvement was new and was exceedingly useful because of the advantage in a large cotton factory of being able to do about double the work in the same space and with a reduction of the labor and power per pound of cotton spun. The change made by the inventor was not a mere duplication of the mechanism of the old machine, because in that case every part of the machinery would have been duplicated; whereas a large portion of it remained unchanged. The change was not a mere change in size of the old machine, because in that case the changed machine would have been about twice as long to accommodate about double the number of spindles; whereas the length of the machine remained substantially the same. The improved machine was patented; was it a patentable combination or an unpatentable aggregation of separate elements? In the Reckendorfer case the court sets forth the proposition that: "The combination, to be patentable, must produce a different force, or effect, or result, in the combined forces or processes, from that given by their separate parts. There must be a new result produced by their union; if not so, it is only an agaregation of separate elements." The word "result" here is evidently intended to mean a single result produced by the combined action of all the elements, because the court illustrates its views by refer

ence to a saw-mill in which the combined action of a saw and a log-carriage produce the single result of a board. In the old fly-frame, however, each separate spindle did its own work; and when the machine was changed by Davoll the additional spindles did not affect in any manner the separate operations of the old spindles in producing yarns, or of the mechanism for driving them, or the separate yarns spun by them, although both the new and the old spindles were combined by the frame of the machine and by the single driving shaft and intermediate gearing which operated them simultaneously. Judged, therefore, by the law of the Reckendorfer case, the Davoll improvement was legally only an aggregation of separate elements. The jury in the case of Davoll v. Brown under the patent, being men of ordinary common sense, were of a different opinion, as they found a verdict for the patentee; and the judge before whom the case was tried appears to have agreed with them. Subsequently a motion came before Judge Woodbury for a new trial on the ground of alleged errors in the charge to the jury and in the specification of the patent; and this motion was refused. Davoll v. Brown, 1 Wood. & M. 53.

Another dictum laid down in the Reckendorfer case is as follows, in reference to the illustrations given by it of patentable combinations: "In these and numerous like cases the parts co-operate in producing the final effect, sometimes simultaneously, sometimes successively. The result comes from the combined effect of the several parts, not simply from the separate action of each; and is, therefore, patentable." The Davoll case is an instance that this proposition is not sound mechanically when applied to machines whose members (the spindles) ope

rate upon articles (yarns) which are separate from each other and constitute separate effects or results.

Let us next consider how this same dictum applies to some machines in which the members operate upon the same material. Take the case of a harvester. The cutting apparatus cuts the grain and then its work upon the article is ended. The platform behind the cutting apparatus receives the cut grain as it falls, but without altering or affecting in any way the operation of the cutters or the cut grain produced by its action, and without aiding the work of cutting. The rake gathers the grain which falls on the platform and discharges it. Now it may properly be said that the platform and the rake co-operate (giving this word the meaning evidently intended by the court from the illustration of the sawmill), the result of their combined action being the gathering of the cut grain and its delivery in a gavel; but what have these two devices to do with the action of the cutting apparatus? Is not this clearly a case where the result produced by the machine comes simply from the separate actions of the cutting apparatus first, and of the combined platform and rake afterwards? Was the man who first combined (using the word in a mechanical sense) an automatic rake with the cutting apparatus and platform of a harvester, an inventor of a patentable combination of cutting apparatus, platform, and rake, or the producer of "only an aggregation of separate elements?" The Supreme Court before the days of the Reckendorfer decision appears to have been of the opinion that the self-raking harvester was a patentable combination, as in the case of Seymour v. Osborne, 78 U. S. 11 Wall. 516, 20 L. ed. 33, they decided that the combination of a cutting apparatus, a platform of a particular form, and

a sweep-rake, was a patentable combination; even when every one of these elements considered separately was not only old, but was found in other but different combinations in older harvesters. The court in this case was undoubtedly governed by the rule of law then practically in force, viz: that the new mode of operation produced by the new combination was conclusive evidence of invention, the new mode of operation being the collective operation of the combination as a whole.

§ 43. Mechanical Difference Between an Aggregation and a Combination.

The difference between an aggregation and a combination is well understood by mechanics and may be illustrated as follows: Let a stool be placed near a table so that a person sitting upon the stool can bear his back against the rim of the table. The function of the stool in this association of devices is to support the weight of the sitter at a convenient distance from the ground; while the function performed by the table is to hold the back of the sitter upright. The two articles are disconnected in the common sense understanding of the term, and neither affects the other or the work done by the other. This is a case of mechanical aggregation. Now assume that the piece of the table or back-rest against which the sitter leaned his back is removed from the residue and is connected with the stool by uprights at one side of the seat. We then have a chair in which the same elements (stool and piece taken from the table) perform the same functions as before, so far as the sitter is concerned; but, in the case of the chair, the piece taken from the table and now constituting part of the chair is sustained in its operating position by the stool,

and the two form members of one compound machine. In this case there is a clear mechanical combination of stool and back-rest, forming the piece of furniture commonly called a chair.

Take again the case of the multiple watch key. The common watch key had a single pipe (for fitting and turning the square winding stem of the watch) combined with a holder for holding and turning the pipe. As the winding stems of different watches vary in size, six different keys of different sizes were required by a watch repairer. Subsequently, six pipes of the progressive different sizes were combined radially with a single holder so as to project from it like the spokes project from the hub of a wheel. The six separate keys when laying side by side on a work bench, or if tied together in a bundle, constituted an aggregation; the six pipes of different sizes connected with one holder which is common to all constitute a mechanical combination. The compound tool was a new and exceedingly useful one, as it saved the time required to take up and put down several of the single keys in order to find one that would fit the watch to be wound. The new tool when first produced was not a mere duplication or multiplication of the old single tool, because in that case it would have had six holders as well as six pipes; nor was it a mere multiplication or duplication of the pipes of any one of the single keys, because in that case its pipes would have all been of the same size. It had a new mode of operation in the mechanical sense, because it had the capacity or property of winding all the different sizes of winding stems, while each of the old keys could wind those of but one size; and this new capacity or property was, mechanically speaking, a new result. The