Plaintiff appellee has moved for the dismissal of this appeal on the ground that appellant has violated the requirement of Appellate Rule 10(c) that the “grouping of exceptions under given assignments of error” be confined to a single issue of law so far as practicable. The appellant has listed 167 assignments of error based upon 168 exceptions to the findings of fact and conclusions of law in the trial court’s order. Although the exceptions and assignments of error have been placed after each issue presented in its brief, appellant, for the most part, has neglected to identify or address them expressly in its argument under each issue. Thus it is virtually impossible to determine whether any exceptions have been abandoned for lack of argument. While we think plaintiff’s position is well taken, we have chosen to discuss the questions raised by this appeal on their merits.
From a substantial record, the court made lengthy and detailed *53findings of fact. This Court must now determine whether those findings are supported by the evidence and whether they support the trial court’s conclusions of law and order. Graham and Son, Inc., v. Board of Education, 25 N.C. App. 163, 212 S.E. 2d 542, cert. den. 287 N.C. 465, 215 S.E. 2d 623 (1975).
 Defendant has excepted to the trial court’s findings that on 15 August 1973 the plaintiff afforded the defendant ample written notice of its claim of a “changed condition” at the work site. Defendant appears to contend that the notice was deficient in that it did not sufficiently detail the nature of the changed condition and the alteration in work procedures which would be necessitated.
In Blankenship Construction Company v. Highway Commission, 28 N.C. App. 593, 222 S.E. 2d 452, disc, review denied 290 N.C. 550,230 S.E. 2d 765 (1976), this Court construed the notice requirement as contained in § 4.3A of the Standard Specifications for Roads and Structures (hereinafter “SSRS”), stating as follows:
In order to qualify for additional compensation under Sections 4.3A or 4.4(c), the Contractor is required to furnish the Engineer written notice of the alleged changed conditions....
While the form of the notice - written or oral - may not be critical, the content of the notice must satisfy the underlying purpose of the notice requirement ____In our opinion the purpose of the notice requirement of Section 4.3A is to apprise the Commission of the Contractor’s belief that he has encountered “work conditions at the site differing materially from those indicated in the contract” for which he is entitled to an “equitable adjustment.”
Id. at 607, 222 S.E. 2d at 461.
We find that the written notice given by plaintiff clearly apprised the defendant of the claim of a changed condition at the work site in compliance with § 4.3A of the SSRS. Plaintiff’s letter of 15 August 1973 explicitly advised the defendant of its claim and demand as follows:
Our contract with you has a changed condition clause. With the schedule demanded and the superior knowledge of *54the Highway Commission and its design engineers, the contract was based on the fact that the soils could be compacted. We believe that the excessive moisture in the soils of this project created by excessive rain and other reasons, the drainage characteristics and soil conditions constitute a changed condition requiring that the Highway Commission grant us equitable adjustment and extension of time.
Pursuant to the specifications and in order to further protect our position in this matter we hereby notify the commission in writing that we are now having and have had since the beginning of this project, a changed condition of which employees of the commission have had knowledge.
In its letter plaintiff further requested a meeting to see if the parties could reach an agreement concerning an equitable adjustment and time extension for a changed condition.
By letter dated 18 September 1973 defendant advised plaintiff that it did not concur with the claim of a changed condition as presented in the 15 August 1973 letter (and as also presented in a joint meeting held 17 September 1973) and denied plaintiff’s request for an adjustment in unit prices or for a time extension. This letter is, of course, a written acknowledgment by the defendant that the plaintiff had informed it of the belief that there had been encountered work conditions at the site differing from those indicated in the contract for which the contractor was entitled to an equitable adjustment.
We find nothing in § 4.3A, or in its interpretation by the Blankenship Court, which would support the defendant’s contention that the contractor in this initial notice was required to spell out in detail the exact nature and extent of the unclassified excavation work it was claiming under a changed condition. At this point in its claim, plaintiff was not required to itemize the fine points and particulars which subsequently would be necessary in the proof of its claim. All that was necessary at this juncture was a “forceful indication of changed conditions and demand for equitable compensation.” Blankenship Construction Company v. Highway Commission, supra. The plaintiff’s letter of 15 August 1973 fully supports the trial court’s *55finding that ample written notice was provided in accordance with the contract.
 Defendant next argues that the trial court erred in granting plaintiff recovery on the basis of “changed conditions” when different theories and claims were presented to the State Highway Administrator. Defendant is correct in its contention that this Court in Inland Bridge Company, Inc. v. Highway Commission, 30 N.C. App. 535, 227 S.E. 2d 648 (1976), held that under N.C.G.S. 136-29, a party may not develop theories of recovery in Superior Court in addition to those set forth in the claim filed with the State Highway Administrator. However, the defendant’s reliance upon the opinion in Inland Bridge is misplaced. The Court’s decision in that case was based upon the following:
Plaintiffs’ whole claim before the Commission was for misrepresentation. Had they desired to sue under the provisions in the SSRS incorporated into the contract, which provides for claims based on changed conditions, extra work, or reclassification of materials, it was necessary for them to elect to do so prior to the trial in the Superior Court. Construction Co. v. Highway Comm., 28 N.C. App. 593, 222 S.E. 2d 452 (1976).
Unlike the contractor in Inland Bridge, in the case at hand the plaintiff contractor did submit in its verified claim letter dated 6 October 1975 a claim for increased compensation due to the encountering of changed conditions. In this letter individual claims were separated into three groups with detailed explanation and supporting data, to wit: contract termination costs; certain excavation costs involving rock borrow, waste excavation, and slide excavation; and costs directly arising from changed conditions and/or defective design. While the tenor of the verified claim is that all categories of increased costs were brought about by the unanticipated conditions encountered, the plaintiff further encompassed the total claim under the last heading of “changed conditions” by the following:
For the purposes of this claim letter, we will state that the amount involved due to changed conditions and/or defective design and specifications, is $814,494.81 plus any *56money not recognized as due the Contractor in other parts of this letter.
Thus, plaintiff, while identifying and categorizing certain claims for the benefit of the defendant, made it abundantly clear that any such claims not recognized in the separate categories as presented were to be included in the overall “changed conditions” claim. Plaintiff did not pursue or recover at trial on a theory which had not been previously presented to the Administrator. Defendant’s further contention, that at trial plaintiff could only attempt to prove its compilation of damages in the one method presented to the Administrator, we find to be without merit.
 Appellant’s next assignment of error involves a fundamental question to be resolved in this action: Whether the plaintiff-contractor in fact and in law encountered “changed conditions” at the work site so as to entitle it to an equitable adjustment in compensation from that specified in the contract. Article 4.3A of the SSRS, incorporated into the parties’ contract, provides in pertinent part as follows:
Should the Contractor encounter or the Commission discover during the progress of the work conditions at the site differing materially from those indicated in the contract, which conditions could not have been discovered by reasonable examination of the site, the Engineer shall be promptly notified in writing of such conditions before they are disturbed. The Engineer will thereupon promptly investigate the conditions and if he finds they do so materially differ and cause a material increase or decrease in the cost of performance of the contract, an equitable adjustment will be made and a supplemental agreement entered into accordingly.
Defendant appellant does not appear to contest that excessive moisture and unstable soils were in fact present at the work site as contended by plaintiff. Abundant evidence was presented at trial of the existence of excessively wet earth materials which forced plaintiff to resort to construction of the fills by means of the “sandwich method” of alternating layers of rock and earth, since the soil would not dry back to achieve the specified density when compacted. Furthermore, plaintiff’s later difficulty in obtaining rock even to continue in this time-consuming and expensive method of construe*57tion was essentially unchallenged by defendant. Although defendant initially refused plaintiff’s request to waste the unsuitable material encountered in the Black Gap cut, it now admits on appeal that there was no question but that the material was too wet in its natural condition for the construction of roadway embankments. All parties acknowledge that the “cave-in” or “slide” in the eastern project,which was caused by wet and unstable soils, necessitated a redesign of this portion of the project and its eventual cancellation.
Since the existence of the above conditions is not in controversy, the basic issue before this Court is whether this situation constituted “work conditions at the site differing materially from those indicated in the contract. ” Defendant does not argue on appeal, nor do we find, that the site conditions should have been discovered by reasonable examination of the area.
In essence the trial court concluded from the facts found that the parties were mutually mistaken at the time of bid as to the soil conditions which actually existed. Quoting extensively from the contract, the court found that the presence of these conditions could not have been anticipated from the contract itself. The trial court held that the contract provisions concerning soil types, compaction and proof rolling requirements, and specifications applicable to embankment construction constituted material representations that the soil conditions present at the work site would be suitable for use as indicated. The contract explicitly represented that for the most part “[s]oils should pose no great problems on this project . . . .” Additionally, the implication that no unsuitable material would be encountered was suggested by the deliberate deletion of Section 22, the standard provision which defines what type of material is to be classified as unsuitable. The court further found that the time period of just sixteen months which was allotted for completion of the entire project was an affirmative indication or representation that this work could be accomplished within the time prescribed. Based upon its finding of mutual mistake of fact, the court concluded that the plaintiff was entitled to an equitable adjustment for additional costs incurred as a direct result of the differing site conditions.
We hold the above findings and conclusions of the trial judge to be supported both by the evidence and the law. In reaching our decision we have considered the analysis of other jurisdictions, both federal and state, as well as our own North Carolina decisions, relat*58ing to the interpretation of construction contracts containing the changed condition clause as found in Section 4.3A of the SSRS.
Contract design features, specifications and requirements have been held in several instances to constitute affirmative indications that the job could be accomplished in the manner designated in the contract and completed within the prescribed time limits. See Southern Paving Corporations, AGBCA No. 74-103, 77-2 BCA ¶ 12,813 (1977); Foster Construction C.A. and Williams Brothers Company v. United States, 435 F2d 873, 193 Ct.Cl. 587 (1970); Ray D. Bolander Company. Inc. v. United States, 186 Ct. Claims 398 (1968)- The Bolander opinion, in considering a differing site condition claim, is particularly instructive as it dealt with detailed contract compaction requirements and other design features similar to those present in the contract now before us. This decision held that the contractor had a valid differing site condition claim based on the positive representations concerning the soil conditions as contained in the contract documents. The Court of Claims stated:
It would be equally inane to suppose that this article on compaction and all the specifications were in this contract for no purpose.
... There was a clear implication (or “indication,” using the word in the “Changed Conditions” article) that these were soils capable of compaction to [the degree specified in the contract]....
Even assuming, arguendo, that the provision on compaction was not a representation, it was at the very least misleading and ambiguous, and the consequences of that ambiguity are chargeable to the author.
Id. at 417.
In Lowder, Inc. v. Highway Commission, 26 N.C. App. 622, 217 S.E. 2d 682, cert. denied 288 N.C. 393, 218 S.E. 2d 467 (1975), a large overrun in undercut excavation occasioned by unexpected and excessive wetness was determined to constitute a “change condition” within Section 4.3A of the SSRS. In its decision the Court specifically stated that “[i]n our opinion the encountering of unexpected excessive wetness may constitute as much a change of condition as the encountering of unexpected rock.” Id. at 644, 217 S.E. 2d at 696. The opinion held that certain contract proposals and plans, in this instance the *59location and quantity of undercut excavation, may constitute material representations which justifiably can be relied upon by a contract- or. When confronted by conditions which significantly differ from those indicated to exist in the contract, the contractor may legitimately seek relief under the “changed condition” section of the contract.
Where parties labor under a mutual mistake as to vital facts, the contract, in the interests of fairness, should be flexible enough to permit an equitable adjustment.
The broad purpose of changed conditions clauses, and, indeed, the purpose of § 4.3A, is to encourage low, competent bids.
“Cost hazards are such in subsurface areas that qualified contractors, prior to the adoption of the article used in standard forms of government contracts, were obliged to make extremely high bids based on the assumption that the worst conditions conceivable would be met in the performance of the work. Drafters of contract forms foresaw greater economy to the government if contractors could be encouraged to bid upon normal conditions, with the assurance that they would be reimbursed in case of abnormal conditions actually encountered and to the extent that they actually increase costs. The revision of the costs due to conditions that are abnormal is accomplished by what the Changes article denominates an ‘equitable adjustment’.” Anderson, Changes, Changed Conditions and Extras in Government Contracting, 42 Ill. L. Rev. 29, 47 (1947).
To ignore this policy is to open the door to disastrous consequences for the State.
Id. at 645, 217 S.E. 2d at 696.
We conclude that the evidence amply supports the trial court’s findings that the parties were mutually mistaken at the time they entered into this contract as to the conditions that were going to be encountered. In addition to the conditions which were indicated in the contract itself, as discussed above, the record is replete with evidence that the earth material prevailing at the work site was not anticipated even by the defendant. Defendant’s Resident Engineer acknowledged that the 16 months allotted to plaintiff to complete its unclassified excavation work, as well as all sequential work, in fact was a rela*60tively “quick completion date.” Further testimony of this witness was to the effect that, notwithstanding the contract provision that for the most part “[s]oils should pose no great problems on this project----,” the soils did present a “considerable problem to this contractor from day one.” The Resident Engineer, in discussing the Black Gap area, stated that “[i]t’s an ordinary assumption that we made that the material coming out of the cut area was supposedly suitable, usable material;” while defendant, in its brief, now concedes that the material encountered in the Black Gap cut “was too wet in its natural condition for the construction of roadway embankments.” Although the soils specialist tendered by plaintiff testified that knowledge as to the moisture content of the soil would have been the most important single piece of information in evaluation of these soils, no such documentation was present in the defendant’s subsurface investigation for this project. This expert testified that in his opinion the contract documents, most particularly the subsoil investigation report, would not have alerted a reasonable and prudent contractor as to the soil conditions which were actually encountered.
Finally, we note that the plaintiff’s bid for this project of $5,311,450.82 was in line with the defendant’s Engineer’s estimate of $5,205,141.67. This was also true of the parties’ respective bid and estimate, $3,370,930 and $3,328,260, for the main bid item of unclassified excavation work. The foregoing is a significant indication that neither the plaintiff contractor nor the defendant had known of or anticipated the unstable and unworkable soil conditions which resulted in the ensuing cost overruns. Southern Paving Corporations, AGBCA No. 74-103, 77-2 BCA 1112,813 (1977).
Based upon the above, we hold the trial court was correct in its determination that the contractor did encounter a changed condition from that indicated in the contract as provided in § 4.3A and was entitled to an equitable adjustment for additional costs incurred.
 Assuming the court was correct in its finding of a changed condition, defendant next argues that plaintiff is barred from recovery of additional compensation by its failure to maintain cost records in accordance with Sections 4.3 and 9.4 of the SSRS. Section 4.3 provides as follows:
In the event that the Commission and the Contractor are unable to reach an agreement concerning the alleged *61changed conditions, the Contractor will be required to keep an accurate and detailed cost record which will indicate not only the cost of the work done under the alleged changed conditions, but the cost of any remaining unaffected quantity of any bid item which has had some of its quantities affected by the alleged changed conditions, and failure to keep such a record shall be a bar to any recovery by reason of such alleged changed conditions. Such cost records will be kept with the same particularity as force account records and the Commission shall be given the same opportunity to supervise and check the keeping of such records as is done in force account work.
Section 9.4 details the manner of payment for work done on a force account basis as follows:
1. Labor. For all labor and foremen in direct charge of the specific operations, the Contractor shall receive the base rate of wages (or scale) actually being paid by the Contract- or for the class or classes of labor normally necessary to perform the work for each and every hour that said labor and foremen are actually engaged in such work, to which rate 30% will be added. Before beginning the work the Contractor shall file with the Engineer for his approval a list of all wage rates applicable to the work. Approval will not be granted where these wage rates are not actually representative of wages being paid elsewhere on the project for comparable classes of labor performing similar work, or where these wage rates include costs paid to or on behalf of workmen by reason of any fringe benefit.
2. Bond, Insurance, and Tax. For property damage, liability, and workmen’s compensation insurance premiums, unemployment insurance contributions and social security taxes on the force account work, the Contractor shall receive the actual cost, to which cost 6% will be added. The Contractor shall furnish satisfactory evidence of the rate or rates paid for such bond, insurance, and tax.
3. Materials. For materials accepted by the Engineer and used, the Contractor shall receive the actual cost of such materials delivered on the work, including transportation charges paid by him (exclusive of machinery rentals as *62hereinafter set forth), to which cost 15% will be added.
4. Equipment. For any machinery or special equipment (other than small tools) including fuel, lubricants, cutting edges, all repairs and all other operating and maintenance costs (other than operator) plus transportation costs for equipment not already on the project, the Contractor shall receive the rental rates listed in the current schedule published by the Associated Equipment Distributors. When equipment is used for a period less than one month, the rental rate shall be computed on an hourly basis using an hourly rate which is 1/176 of the monthly rate. When equipment is used for a period of one month or more, the rental rate shall be on a monthly rate basis.
5. Miscellaneous. No additional allowance will be made for general superintendance, the use of small tools, or other costs for which no specific allowance is herein provided.
6. Compensation. The Contractor’s representative and the Engineer shall compare records of the cost of work done as ordered on a force account basis.
7. Statements. No payment will be made for work performed on a force account basis until the Contractor has furnished the Engineer with duplicate itemized statements of the cost of such force account work detailed as follows:
a. Name, classification, date daily hours, total hours, rate, and extension for each laborer and foreman.
b. Designation, dates, daily hours, total hours, rental rate, and extension for each unit of machinery and equipment.
c. Quantities of materials, prices, and extensions.
d. Transportation of materials.
e. Cost of property damage, liability and workmen’s compensation insurance premiums, unemployment insurance contributions, and social security tax.
Statements shall be accompanied and supported by receipt*63ed invoices for all materials used and transportation charges. However, if materials used on the force account work are not specifically purchased for such work but are taken from the Contractor’s stock, then in lieu of the invoices the Contractor shall furnish an affidavit certifying that such materials were taken from his stock, that the quantity claimed was actually used, and that the price and transportation claimed represents the actual cost to the Contractor.
The procedures under the foregoing provisions for obtaining additional compensation based on changed conditions were discussed in Blankenship Construction Company v. Highway Commission, 28 N.C. App. 593, 222 S.E. 2d 452, disc. review denied290 N.C. 550, 230 S.E. 2d 765 (1976). The Court defined the basic obligations of the Contractor as (1) insuring that notice of its intended claim is given to the Engineer or Commission, (2) maintaining accurate and detailed cost records with the ‘ ‘particularity of force account records, ” and (3) providing the Commission the opportunity to supervise the keeping of its records. Construing the policy of Section 4.3, the Blankenship Court emphasized that the State must be given the chance to supervise and check records as the work progresses in order to protect itself from a claim based on inaccurate cost estimates.
As discussed heretofore, we agree with the trial court that sufficient notice of its intended claim was properly given by the plaintiff. We also find that accurate and detailed cost records were maintained during the course of the work and that defendant was given ample opportunity to oversee these records had it desired to do so.
The foreman’s daily reports, maintained under the supervision and review of the plaintiff-contractor’s job superintendent, constitute the base source and record of the contractor’s cost of performing its unclassified excavation work. These reports, consisting of fourteen volumes, record the following information: weather conditions, the name of each operator and the particular piece of equipment he was operating, the actual hours each operator worked, the actual hours each piece of equipment was working, and the actual hours each piece of equipment might have been idled. On the back of each such report the accompanying information was recorded: the actual cut and fill station numbers where the equipment was working, usually the distances of the hauls, the quantity of unclassified excavation moved, and then any pertinent remarks with respect to the nature of the work *64tion material being encountered, and the repairs required for any piece of equipment which was idled as a result of a breakdown. Costs, including labor, equipment and material costs, were maintained on a monthly basis on the contractor’s computer. Proper percentages in accordance with Section 9.4 were added to the labor and materials costs and for insurance, bond and taxes. Although the compilation of total costs presented at trial was prepared in part by later substituting the applicable AED equipment rate for the plaintiff’s “in house” costs, the costs were maintained currently with the work performed. They required only a procedural rate substitution for the equipment costs upon defendant’s request at any time to be in the form prescribed by Section 9.4. Plaintiff’s costs for additional rock borrow required by the unstable soil conditions were established at a set unit price in a supplemental agreement covering rock borrow from the same source. Costs for demobilization of equipment, due to the unexpected termination of the work necessitated by the changed conditions, were submitted to defendant based upon the percentage of unclassified excavation not completed on the project.
The Area Engineer for the contractor, who was on the project during performance from two to three days each month, monitored and compiled the contractor’s extra costs associated with the changed conditions. Concerning the accuracy of these records and compiled costs, defendant’s Resident Engineer testified as follows:
I would agree that the contractor kept good account of where equipment was working and what it was doing, even prior to that time (the date of notice of changed condition), on those daily reports. I would agree that Groves kept pretty good records out on the job ... . They kept good records on production rate out on the job .... If you were satisfied they were accurate records, as long as you had a daily record or when and where equipment was working, the dollar figures could be put on those records at any time. I don’t have any reason to question their records about actually where equipment was, how many hours it was working and what it was doing each day.
With respect to the foregoing, the trial court made the following findings not excepted to by appellant:
That the plaintiff had always during this project maintained detailed daily labor and equipment reports. That the
*65daily reports reflected the total hours of all equipment and labor for a particular day and reflected what the men and equipment were actually doing, i.e., unclassified excavation, force account, blasting, etc.
Although the above records and costs were maintained by plaintiff during the course of the work performed, defendant consistently declined any opportunity to supervise and check the records which it now contends are inadequate. Defendant’s Resident Engineer testified that at the parties’ cost records meeting of 2 October 1973, he was shown how the records were going to be kept. He acknowledged that, even though the plaintiff kept “pretty good records out on the job” and advised him that printouts on the costs from the daily records could be obtained on a weekly basis, he did not request the computer printout or review the daily records on a regular basis. Significantly, this same witness testified that since he did not consider the project work to be affected by any changed condition, “[a]fter the meeting I really wasn’t too much interested in what he was going to do with his records.” Not only did the defendant fail to request that plaintiff alter its method of record keeping during progress of the work, it actually encouraged plaintiff, by letter dated 4 October 1973, not to keep records as if by force account, asserting such documentation would be “impractical” and “not render anything useful to either party.” We find the record fully supports the trial court’s finding that the defendant ignored the opportunity to review the record keeping of the plaintiff after being given notice of the asserted changed condition on 15 August 1973.
Inasmuch as the record supports the findings that plaintiff did keep accurate and detailed records with the particularity of force account records and that defendant was in fact provided the opportunity to review these records, which opportunity it disregarded, we find this assignment of error to be without merit.
 We further find no merit in defendant’s contention that the court improperly admitted into evidence plaintiff’s Exhibits 18 and 19(b), respectively, consisting of the daily work reports and the total extra costs compilation based on these reports. For reasons discussed previously, Sections 4.3 and 9.4 of the SSRS present no bar to the admission of these documents. We also find the records and compilation admissible into evidence under the business entries exception to the hearsay rule.
The admissibility requirements for such documents were set forth in Lowder, Inc. v. Highway Commission, 26 N.C. App. 622, 217 *66S.E. 2d 682, cert. denied 288 N.C. 393, 218 S.E. 2d 467 (1975): (1) the entries must be made in the regular course of business, (2) the entries must be made contemporaneously with the events recorded, (3) the entries must be original entries, and (4) the entries must be based upon the personal knowledge of the person making them. Records compiled under the above specifications are admissible into evidence since the circumstances indicate that they are sufficiently “reliable and trustworthy as to reflect accurately the actual costs incurred.” Id. at 650, 217 S.E. 2d at 700.
Plaintiff’s Exhibit 18, the foreman’s daily reports, was the base source for the compilation of damages and recorded the labor and equipment hours expended in the unclassified excavation work. It meets the business entries exception to the hearsay rule in that (1) appellant’s counsel stipulated they were original entries kept under the contractor’s job superintendent’s supervision, (2) the entries were made in the regular course of business, (3) the entries were made contemporaneously with the events recorded, and (4) the entries were based upon the personal knowledge of the persons making them. Their reliability and trustworthiness were acknowledged by defendant’s Resident Engineer who testified that “Groves kept pretty good records out on the job” and that he did not have “any reason to question the records about actually where the equipment was, how many hours it was working and what it was doing each day.” Plaintiff’s Job Superintendent testified that he reviewed these labor and equipment reports each day for accuracy.
We find plaintiff’s Exhibit 19(b), the compilation of costs, admissible for the same reasons discussed above. This document was based upon Exhibit 18. See Lowder, Inc. v. Highway Commission, supra. Since the costs for the unclassified excavation work had been maintained on plaintiff’s computer at the time the work was performed, all that was necessary in its preparation was the recomputation of equipment costs' from “in-house” rates to AED rates. This document also meets the tests of trustworthiness and reliability. We do not consider defendant’s attempt to raise for the first time on appeal its objection to this exhibit as being a computer record.
 Defendant also assigns error to the court’s ruling that the plaintiff was entitled to recover from the defendant all liquidated damages previously withheld. These damages were assessed pursuant to the following special provision of the contract:
*67Liquidated damages of one hundred dollars ($100.00) will be charged the contractor for each calendar day after October 1, 1973, that the project from station 1029+04 to station 30+00 (including -Y- lines and driveways) is not complete to the extent that the pavement is placed, the shoulders are constructed, the guardrail is installed, and two-way traffic is placed and then maintained on same.
Under this clause, plaintiff was assessed liquidated damages in the sum of $15,500.00.
Obviously, as an elementary general proposition, a contractor is not liable under a clause for liquidated damages based on a time limit if his failure to complete the contract within the specified time was wholly due to the act or omission of the other party in delaying the work, whether by omitting to provide the faculties (sic) or conditions contemplated in the contract to be provided by him, or by those for whom he is responsible, or by interfering with the work after the contractor has begun, or otherwise. Dunavant v. R.R., 122 N.C. 999, 29 S.E. 837; United States v. United Engineering & Contracting Co., 234 U.S. 236, 58 L.ed. 1294; Anno. 152 A.L.R., p. 1350; 22 Am. Jur., 2d, Damages, § 233; 25 C J.S., Damages, p. 1096. The concept of justice back of the decisions appears to be that the other party should not be allowed to recover damages for what he himself has caused.
The record contains plenary evidence to support the trial court’s finding that “the completion date of October 1,1973 for the first phase of the project would have been met by the plaintiff had it not encountered the changed conditions and been granted the proper extensions of time.” Defendant’s Resident Engineer testified that as of 8 June 1973 the plaintiff was 90% complete on the first phase. However, it was at this point that plaintiff had depleted all available sources of rock and was left with soil which was too wet to be used without rock for embankment fills. Under these conditions, the contractor requested in several meetings that it be allowed to waste this unsuitable material. As testified to by the Resident Engineer, defendant denied the request, contending that the material was in fact suitable since it *68was indicated to be so in the contract. The plaintiff’s request was denied even though the Resident Engineer later testified that at this same time the “material at Black Gap was wet when it came out of the cut... and it seemed to get wetter the further we went down into it.” This witness also testified that if the contractor had been allowed to waste the material in June as he requested, there was no doubt he could have finished the project sooner, possibly by the 1 October completion date. Even when the project was behind schedule, the Resident Engineer stated that he was completely satisfied with the work effort being expended by the contractor. In the latter part of October defendant finally realized that the unsuitable soil in the Black Gap cut was preventing any completion of the project, and plaintiff was allowed to waste this material as he had requested months earlier.
By its refusal to allow plaintiff to waste the unsuitable material when initially requested, coupled with its knowledge that the wet, unstable soil could not be utilized as indicated in the contract, defendant clearly waived any expectation of adherence to the contract schedule. See, Graham and Son, Inc. v. Board of Education, 25 N.C. App. 163, 212 S.E. 2d 542, cert. denied 287 N.C. 465, 215 S.E. 2d 623 (1975). On the basis of these facts, defendant was not entitled to assess liquidated damages and the court properly ordered their recovery by plaintiff.
 By its next assignment of error, defendant contends the trial court erroneously calculated the credits for payments made by the Board of Transportation to the plaintiff-contractor. As to the finding submitted on appeal which defendant now asserts would have been a correct calculation of credit, we note at the outset that the record contains no request by defendant to the trial court to make such a finding. Defendant should have requested the court to make the finding and excepted to its failure to do so. This proposed finding of fact is therefore not before us for consideration. Logan v. Sprinkle, 256 N.C. 41, 123 S.E. 2d 209 (1961). Although defendant has properly included in its brief the assignments of error and exceptions to the findings of fact in which the trial court calculated the disputed credits, it has completely failed to afford this Court any citations of authority or the portions of the record upon which it relies to support its argument. Accordingly, under Appellate Rule 28(b) (3) its argument is deemed abandoned. State v. Minshew, 33 N.C. App. 593, 235 S.E. 2d 866 (1977); State v. Tuttle, 33 N.C. App. 465, 235 S.E. 2d 412 (1977). This Court will *69not “fish out” an appellant’s exception which is not properly presented. Lee v. Tire Co., 40 N.C. App. 150, 157, 252 S.E. 2d 252, 257 dis.
We conclude that the court’s findings of fact are supported by competent evidence and support the court’s conclusions of law.
 We do, however, find merit in defendant’s contention that the court erred in awarding to plaintiff compensation for its expert witnesses. We are aware that the trial court did find that the expert witnesses “were required” to be present during the entire trial. However, as conceded by plaintiff in its brief, no subpoenas for these witnesses are to be found in the record. Under existing case law, the trial judge was therefore without authority to tax the expert witness fees against appellant as a portion of the costs. State v. Johnson, 282 N.C. 1, 191 S.E. 2d 641 (1972), aff'd 286 N.C. 331, 210 S.E. 2d 260 (1974); Siedlecki v. Powell, 36 N.C. App. 690, 245 S.E. 2d 417 (1978); Redevelopment Commission of Winston-Salem v. Weatherman, 23 N.C. App. 136, 208 S.E. 2d 412 (1974).
We have considered defendant’s remaining assignments of error and find them to be without merit.
That portion of the judgment ordering the defendant to pay expert witness fees is reversed. The remainder of the trial court’s judgment is affirmed in its entirety.
Affirmed in part and reversed in part.
Judges Clark and Erwin concur.
Judge ERWIN concurred in this opinion prior to 31 October 1980.