the radiant heat and the air heat produced by different methods of heating and different proportions between radiated surface and exposure factor. This is a very wide subject which has been hardly touched. So far as I am aware, there is no information available on this matter at all, and it is practically virgin soil.

"I have designed a number of instruments for investigating it thoroughly, some of which I explained in a paper read to the Institution during last year, and I exhibited the apparatus itself during the lecture on October 13 at the College. With this apparatus we intend during the present session to tackle the whole problem, in the effort to arrive at some figures and some definite information regarding it.

"Another chief branch of the research work which will be carried out during this year, if we can get enough students to take an interest in it, will be in connection with ventilation matters pure and simple. We intend to investigate and verify, so far as is possible, the co-efficients which are in common use and which were determined by Rietschel at Charlottenburg several years ago. In this connection there is a mass of German literature to translate which has some bearing on the matter, and some of which I think should be published for the benefit of English readers.

"We have erected an apparatus for standardizing air resistances and measuring those resistances on the lines of the electrical Wheatstone bridge. I think this investigation promises well, but I shall be in a better position in six months' time to say something about it.

"Mr. Pearson has very kindly given us a boiler and a set of radiators with which I have erected an apparatus especially designed to exhibit the variations in the rate of flow of water in pipes and the bearing which this difficult problem has on the relative pressures througout a hot water apparatus. We hope this plant will be most instructive, and will enable rules for pipe sizing to be established by experiment. The theory on which this is based is one of my own. It is set out in my book. There is no apparatus in existence on which it can be verified except this, so far as I know.

for testing the effect of various quantities and conditions of air on human beings; also a plant for calibrating the microanemometer which I have designed and had made during the session.

"We have also designed and erected a plant for measuring with great accuracy the value of non-conducting compositions.

"We have erected a complete plant for the investigation of friction of air in pipes."

LEGAL DECISIONS

Agreement to Furnish Steam-Construction.

A provision of a lease of laundry premises provided that the lessor should furnish without charge "live steam pressure through a 1-in. pipe as constructed from the boiler room at the present time." In injunction proceedings by the lessee to restrain the lessor from cutting off the steam, it was held that this did not preclude the lessor from removing the existing 12-in. pipe and replacing it by a 1-in. pipe, in the absence of fraud, accident, or mistake in the execution of the lease. The lease was silent as to the pressure to be maintained. Evidence to show how much steam was being furnished when the lease was made, and how much the defendant continued to furnish thereafter was held to be admissible to show the intent of the contracting parties. The lessee was entitled to receive a live steam pressure through a 1-in. pipe, in amount sufficient to meet the reasonable requirements of his business and increases consequent on the installation of additional machinery, as contemplated by the contracting parties.-Bauer vs. Byrd, Pennsylvania Supreme Court, 91 Atl. 847.

Warranties-Evidence-CounterclaimsBurden of Proof.

A contract for the installation of a heating and ventilating system in a schoolhouse contained the guaranty that the system would, with proper care in operation, heat the schoolroom to 70° F. during the coldest weather and provide good ventilation during school hours. Under this contract a heater was installed which was accepted as being satisfactory. The heater was afterwards used to some extent during the winter of 1912-13. Under a claim that it did not operate satisfactorily, the school district refused to pay therefor, and the contractor brought suit. The defendant counterclaimed for $300 as damages for a breach of the warranty. The defendant recovered a verdict of $75. The plaintiff appealed.

On appeal it was held that, as it was the contention of the plaintiff that the heater had not been properly operated, evidence was admissible that other apparatus, similar in character to the one which the plaintiff had sold to the defendant, when properly operated, satisfactorily heated the buildings in which they were installed. It was also held that in a case like this, where the heating system contracted for was delivered by the plaintiff and accepted by the defendant as in accordance with the contract and warranty, and the defendant relied upon an affirmative defense, the burden of proof rested upon the defendant to establish the defense relied upon -in this case a breach of the warranty as to what the furnace would do under proper care in operation. The judgment was reversed, and a new trial ordered.-Waterman-Waterbury Co. vs. School Dist. No. 2, Michigan Supreme Court, 148 N. W. 673.

Substantial Compliance with Contract.

Suit was brought upon an oral contract, for the price of $380, for furnishing all the material and doing all the work in installing in the building of the defendant a heating plant, consisting of boiler, radiators, pipes, etc., complete. The defense was that the plaintiff's contract required him to furnish a Cambria boiler, with all necessary piping, radiators, etc., and install it in the defendants' building, and that the plaintiff guaranteed the plant to propertly heat the building; that the plaintiff set up a Simplicity boiler instead of Cambria heater and that the defendant did not consent to this change of heaters, and that having made the change on his own motion, the plaintiff's guaranty extended to the Simplicity heater in all respects as it was originally made in regard to the Cambria. At the trial the plaintiff offered evidence tending to prove that the defendant had authorized and ordered the installation of the Simplicity heater at his own risk on the guaranty of the manufacturers of that furnace. The defendant then shifted his ground by admitting that the heater was probably all right, but that the rest of the heating system was not properly installed. He contended that there was something wrong with the connections so that the system would not heat the building, and therefore the plaintiff had not substantially complied with his contract and was not entitled to recover any part of the $380.

The plaintiff offered considerable testimony tending to show a substantial compliance with his contract. It was therefore held that the main questions were of

fact and were for the jury. If there was an honest, substantial compliance with the contract, with minor defects which could be readily supplied, the plaintiff could recover and the jury would make a deduction of such an amount as would remedy the defects. But if there was not an nonest, substantial compliance with the contract the plaintiff could not recover at all. The jury found for the amount of the contract price, with interest less an allowance of $45 for making changes.-Kull vs. Middleman, 51 Pennsylvania Superior Court, 137.

Operating Heating Systems Under a Partial Vacuum.

The question is often asked, is it possible to operate a steam heating apparatus under a partial vacuum?

It is quite difficult to do so successfully and practically impossible to operate under the degree of vacuum that should be maintained to produce the proper results. Assume an outside temperature of 20° F. For this condition the amount of vacuum that should be carried on the radiators to prevent overheating is 161⁄2 in., a condition which it is practically impossible to maintain, as before remarked.

Example: Steam at a temperature of 220° F., room 70° F. Radiation installed, 100 sq. ft. of pipe coil assumed as necessary to heat the room to 70° with an outside temperature of zero.

220 70 = 150° F. temperature differ

ence.

Extensive Ventilation Experiments Arranged by New York Ventilation Commission.

An elaborate series of tests extending over a period of two years will shortly be undertaken upon 60 or more school children of the Bronx, New York, by the New York State Commission on Ventilation, with a view of solving the problem of efficient ventilation for the city's schools.

As previously reported, preliminary experiments have been going on for the last nine months in a specially-constructed experimental chamber at the City College. Five volunteer students from the college have been subjected daily to varying temperatures and states of humidity, as well as to different methods of ventilation, and the work that they were able to accomplish under these conditions has been carefully noted. With the knowledge gained in this way the commission is now ready to transfer its investigations to the school children.

The

The tests will be made in Public School 51, soon to be opened in the Bronx. new building, one of the finest in the city, will contain two classrooms fitted with every conceivable ventilating appliance as well as an elaborate plant for furnishing whatever changes in temperature and air the investigators may desire. Each room will have double ceilings, walls, and floors, in order to provide inlets and outlets for air at any point, but aside from this special mechanical equipment, the rooms will differ in no way from the other classrooms in the building. There will be seats for about thirty children in each, and the youngsters will be kept at their regular classroom work without disturbance. Probably they will not even be aware that they are being made the subjects of scientific tests, although there will not be a minute of the day they will not be under observation.

PSYCHOLOGICAL TESTS ALSO

Members of the commission will make periodic visits to the school, and regular physical examinations will be made to determine the effect of the tests upon the children's health. Psychological tests will also be made to determine the mental efficiency of the youngsters, and the teachers will also be expected to note what effects the tests have upon the class work.

The commission will keep one representative in constant charge of the school plant. This part of the work will be left to Butler P. Crittenden, assistant engineer in charge of the experiments at City College. The members of the commission, all of whom serve without pay, are Prof.

C. E. A. Winslow, College of the City of New York, chairman; Prof. E. L. Thorndyke, psychologist of Teachers' College; Dr. Frederick S. Lee, physiologist of the College of Physicians and Surgeons; D. D. Kimball, engineer; Dr. James Alexander Miller, a physician, and Prof. E. B. Phelps, chemist in the Hygiene Laboratory of the Government Health Service, Washington, D. C.

In discussing the forthcoming tests, Prof. Winslow said:

"Our tests at Public School 51 will put into practice some of the lessons we have learned from the tests at City College. There are those who contend that it is a waste of time and money to install ven< tilating systems at all, and that the best way to get fresh air is to throw open the window. One of the largest private schools in the city has been built on this principle, upon the advice of a prominent physician.

"Then there are those who believe in putting cloth frames in the windows and letting the air filter in that way. Others would have the air let in at the top of the room and taken out at the bottom, and still others argue that it should be just the other way around-let in at the bottom and drawn off at the top. There are so many theories that the only way to settle the question is to put them all to the test.

"That is just what we intend to do, and by observing closely how the children get along in their studies and in their health we hope to arrive at the best method of supplying fresh air in the public schools."

Plans for International Engineering Congress Going Forward.

A report having been circulated to the effect that the International Engineering Congress was to be abandoned, the Committee of Management has issued a bulletin stating that this is not correct and that the congress will be held in San Francisco as scheduled, from September 20 to 25, 1915. Previous to the beginning of the European war, the total number of papers contemplated was about 290. While it is expected that a portion of these will not now be secured, especially those apportioned among the nations now at war, it is believed that by substituting other papers that have been offered, the general plans of the congress may be carried out with a minimum of change.

The present plan is to divide the congress into ten or more sections which will hold their meetings in the new Auditorium Building in the Civic Center of San Fran